Lynn Nolan Ryan, Jr. (born on January 31, 1947), nicknamed "The Ryan Express", is a former Major League Baseball pitcher. He is currently part-owner and team president of the Texas Rangers.

During a major league record 27-year baseball career, he pitched in 1966 and from 1968–1993 for four different teams: the New York Mets, California Angels, Houston Astros, and Texas Rangers. He was inducted into the Baseball Hall of Fame in 1999.

Ryan, a hard-throwing right-handed pitcher, threw pitches that were regularly recorded above 100 miles per hour (160.93 km/h), even past the age of 40.

While his lifetime winning percentage was a relatively pedestrian .526, Ryan was an eight-time MLB All-Star, and his 5,714 career strikeouts rank first in baseball history. He leads the runner-up, Randy Johnson, by 839 strikeouts. Similarly, Ryan's 2,795 bases on balls lead second-place Steve Carlton by 962—walking over 50% more hitters than any other pitcher in Major League history. He is currently the only major league baseball player to have his number retired by 3 different teams: the Angels, Astros, and Rangers (other than Jackie Robinson whose number was retired by the entire MLB).

Ryan is the all-time leader in no-hitters with seven, three more than any other pitcher. He is tied with Bob Feller for most one-hitters, with 12. Ryan also pitched 18 two-hitters. Despite the seven no-hitters, he never threw a perfect game, nor did he ever win a Cy Young Award.

Ryan was born in Refugio, Texas, the youngest of six children, to Lynn Nolan Ryan, Sr. and Martha Lee Hancock Ryan. His family lived in nearby Woodsboro, Texas until they moved to Alvin, Texas when he was 6 weeks old. As a young boy, he enjoyed throwing objects at any target. His father thought that baseball was a better usage for his arm, therefore he encouraged Nolan to play the game.

Ryan joined Alvin Little League Baseball when he was nine, and pitched the first no-hitter of his life a few years later. Ryan also played various positions besides pitcher

In 1965, after graduating from Alvin High School, Ryan was drafted by the New York Mets in the 12th round of the 1965 Major League Baseball Draft. He was assigned to a minor league team in the Appalachian League called the Marion Mets in Marion, Virginia. When Ryan was called up to the New York club the following year, he was the second-youngest player in the league. His first strikeout victim was Pat Jarvis, and he gave up his first major league home run to Joe Torre, a future big-league manager.

Ryan missed much of the 1967 season due to illness, an arm injury, and service with the Army Reserve, pitching only 7 innings for the Mets' minor league affiliate in Jacksonville. Ryan did not stick in the majors for good until the 1968 season. Despite his fastball, he was unable to crack the Mets outstanding pitching rotation, led by Tom Seaver and Jerry Koosman. Ryan was used more as a reliever and spot starter by the 1969 Mets. To deal with frequent blisters on his throwing hand he often soaked his fingers in pickle brine, although the technique's effectiveness was questioned both by Ryan's teammates and coaches.

Ryan pitched well in the 1969 postseason for the Mets. Against the Braves in the NLCS, Ryan completed a Mets sweep by throwing seven innings of relief in Game 3, getting his first playoff win (it would take him 12 years to get another). Then in the 1969 World Series, Ryan saved Game 3, pitching 2? shutout innings against the Baltimore Orioles. The Game 3 victory gave the Mets a 2–1 lead in the Series, which they went on to win in five games. It would be Ryan's only World Series appearance in his career.

On April 18, 1970, Ryan tied a Mets record by striking out 15 batters in one game. Four days later, Ryan's teammate, Tom Seaver, topped it with 19 against the San Diego Padres. Ryan has credited his time with Seaver and the Mets with turning him from just a flamethrower to a pitcher. However, by 1971 Ryan had become increasingly frustrated and was considering retiring from baseball. His record for the season was 10–14. He told Mets management that he was not happy in New York and requested a trade.

Nolan Ryan's number 30 was retired by the California Angels in 1992. 

On December 10, 1971, Ryan was traded to the California Angels along with pitcher Don Rose, catcher Francisco Estrada and outfielder Leroy Stanton for shortstop Jim Fregosi (who would later manage Ryan in Anaheim). Fregosi had been an All-Star in six of seven seasons between 1964 and 1970, but he was past his prime, played fewer than 150 games for the Mets, and never had a good season again. The deal remains controversial, and has been cited as one of the worst in Mets history. It has been argued that in light of his ineffectiveness and unhappiness as a Met, had Ryan not been sent to another organization, he would have continued to struggle with his control. The move was not viewed as unreasonable at the time. However, the transaction quickly turned sour for New York.

In his first season with the Angels, Ryan, given a chance to pitch regularly as a starter for the first time in his career, had a league-leading 329 strikeouts—nearly a third more than the AL runnerup, and to that point, the fourth-highest total of the 20th century. Within five seasons, the season would only be Ryan's fourth-highest strikeout total. He also set a still-standing Major League record by allowing only 5.26 hits per nine innings, breaking Luis Tiant's 5.30 in 1968, as well as posting a 2.28 earned run average that year, to date the second lowest in franchise history, trailing only Dean Chance's 1.65 in 1964. Though Ryan's actual winning percentage hovered only slightly over .500, his strikeouts and no-hitters brought him media attention. Meanwhile, Fregosi failed to produce as a Met, making no significant contribution to the Mets' 1973 pennant-winning campaign; he was sold to the Texas Rangers mid-season.

Although the Angels were a sub-.500 team and remained one for much of his time there, Ryan managed to post some winning records, notably 19–16 in 1972, 21–16 in 1973 and 22–16 in 1974 (the 22 wins tied what remains the Angels franchise record, set by Clyde Wright in 1970). Ryan also led the league in losses in 1976 with a 17–18 record (one short of the franchise record for losses). In the early 1970s, many teams used a four-man rotation and expected the starter to complete the game; thus most games Ryan started ended in a decision.

On July 9, 1972, Ryan struck out three batters on nine pitches in the second inning of a 3–0 win over the Boston Red Sox; he became the seventh American League pitcher to accomplish the nine-pitch/three-strikeout half-inning, and the first (and currently only) pitcher in Major League history to accomplish the feat in both leagues. (On April 19, 1968, he had struck out three batters on nine pitches in the second inning of a 2–1 win over the St. Louis Cardinals; becoming the eighth National League pitcher and the 14th pitcher in Major League history to accomplish the feat.)

In 1973, Ryan set his first major record when he struck out 383 batters in one season, beating Sandy Koufax's old mark by one. Remarking on this feat, Koufax joked, "Yeah, and he also surpassed my total for bases on balls in a single season by 91. I suspect half of those guys he struck out swung rather than get hit."

Ryan threw two no-hitters in 1973. In the second one, on July 15 against the Detroit Tigers, he struck out 17 batters - most in a recorded no-hitter. Ryan was so dominant in this game, it led to one of baseball's best-remembered pranks. Tiger first baseman Norm Cash came to the plate with two outs in the bottom of the ninth, having already struck out three times, and was carrying a clubhouse table leg instead of a bat. Plate umpire Ron Luciano ordered Cash to go back and get a regulation bat, to which Cash replied, "Why, I won't hit him anyway!" With a regulation bat in hand, Cash did finally make contact, but popped out to end the game.

Ryan added a third no-hitter in 1974 and a fourth in 1975, tying another of Koufax's records. In 1974 he twice struck out 19 batters, tying Tom Seaver and Steve Carlton for the single-game record for a nine-inning game. Roger Clemens would become the first pitcher with a 20-strikeout game in 1986.

The California Angels finally made the playoffs in Ryan's eighth and final year there in 1979. He started Game 1 of the ALCS and threw seven innings against the Orioles' Jim Palmer, but neither man was involved in the decision as Baltimore won in the 10th inning. Ryan was scheduled to pitch Game 5, but the Angels were eliminated in four. The season complete, Ryan became a free agent.

Ryan led the American League in strikeouts seven times during his eight seasons with the Angels. However, he also led the league in walks in six of those years, and finished second the other two seasons: 1975 and 1979. Aside from Bob Feller in 1938, Ryan is the only man since 1900 to walk 200 batters in a season, which he did twice: in 1974 and 1977.

Though Ryan's strikeouts and no-hitters got him considerable media attention, he did not win over Angels general manager Buzzie Bavasi, who dismissed him as a flashy .500 pitcher (Ryan was 26–27 in the two years both were with the Angels). When Bavasi let Ryan leave after a 16–14 record in the 1979 season, Bavasi remarked he only needed to replace Ryan with two 8–7 pitchers, adding, "I think my plumber could do that." He later admitted that not re-signing Ryan was his biggest mistake as the Angels general manager.

Nolan Ryan's number 34 was retired by the Houston Astros in 1996. 

Ryan signed a lucrative free-agent contract with the Houston Astros after the 1979 season. The normally light-hitting Ryan got his Houston years started with a bang in a nationally televised game against the Los Angeles Dodgers on April 12, 1980, when he hit a three-run home run off Don Sutton. It was the first of two homers in Ryan's career and produced half of the six RBI he would get that year. On July 4 of that season, at Riverfront Stadium, Ryan recorded his 3,000th career strikeout, the victim being César Gerónimo of the Cincinnati Reds (Gerónimo had also been Bob Gibson's 3,000th strikeout victim, in 1974). Ryan got his third taste of postseason play in 1980, but the Astros were stopped one game short of the World Series.

In the 1980 NLCS versus the Philadelphia Phillies, Ryan pitched well in Game 2, leaving the game tied 2–2 in the seventh (having contributed to both Astros runs with a run scored following a walk, and a sacrifice bunt leading to a run) but again got a no decision in a game that went extra innings. In the fifth and final game of the series, Ryan and the Astros held a 5–2 lead entering the 8th inning. But Ryan allowed three consecutive singles before walking in the third run. The Houston bullpen allowed the Phillies to take a 7–5 lead, and only a game-tying Astro rally permitted Ryan to escape the loss.

Nolan Ryan "bringing it" to Brett Butler in an Astros game at Atlanta in 1983.On September 26, 1981, Ryan threw his fifth no-hitter, breaking Koufax's mark while becoming the third pitcher to throw a no-hitter in each league. That season, his 1.69 ERA won the National League ERA title.

Facing the Los Angeles Dodgers in the 1981 NLDS, Ryan threw a complete game 2-hitter in the opener, outlasting the Dodgers' rookie sensation Fernando Valenzuela. It was Ryan's second and last career postseason win. In the fifth and final game of the series, Ryan left trailing 3–0 and took the loss.

By the end of the 1982 season, both Ryan and Steve Carlton were approaching Walter Johnson's all-time strikeout record, sometimes passing one another's career totals in successive starts. On April 27, 1983, Ryan won the race with his 3,509th whiff, against Brad Mills of the Montreal Expos (Steve Carlton would reach the same mark two weeks after Ryan).

In 1986, Ryan's Astros faced the New York Mets in the National League Championship Series. Ryan had a shaky start in Game 2, taking the loss. He returned in Game 5, throwing 9 innings of 2-hit, 1-run, 12-strikeout ball. However, one of those hits was a Darryl Strawberry home run which tied the game at 1–1, as Dwight Gooden matched Ryan pitch for pitch. Ryan got a no-decision as his Astros lost in 12 innings.

In 1987, Ryan led the major leagues in both ERA (2.76) and strikeouts (270) at the age of 40—but finished 8-16 as the result of extremely poor run support. Despite his .333 winning percentage, Ryan tied for 5th place in the 1987 Cy Young voting.

Nolan Ryan's number 34 was retired by the Texas Rangers (baseball) in 1996.