Timothy Raines Sr. (born September 16, 1959), nicknamed "Rock", is an American professional baseball coach and former player. He played as a left fielder in Major League Baseball for six teams from 1979 to 2002 and was best known for his 13 seasons with the Montreal Expos. A seven-time All-Star, four-time stolen base champion, and National League batting champion, Raines is regarded as one of the best leadoff hitters and baserunners in baseball history. In 2013, Raines began working in the Toronto Blue Jays organization as a roving outfield and baserunning instructor. In 2017, Raines was inducted into the Baseball Hall of Fame.

Raines was born on September 16, 1959, in Sanford, Florida, to Ned and Florence Raines. He attended Seminole High School in Sanford. Raines was one of seven children. Two of his brothers, Levi and Ned III, played minor league baseball. As a baseball player at Seminole, Raines stole home plate ten times. He also rushed for 1,000 yards in eight football games and set two school track and field records that lasted for several years. Raines reportedly received over 100 scholarship offers to play college football.

The Montreal Expos selected Raines in the fifth round of the 1977 Major League Baseball draft. After debuting with six games as a pinch runner in 1979, he played briefly as a second baseman for the Expos in 1980 but soon switched to playing the outfield, and rapidly became a fan favorite due to his aggressiveness on the basepaths. In his strike-interrupted 1981 rookie season, he batted .304 and set a then Major League Baseball rookie record with 71 stolen bases, breaking the previous mark of 56 steals set by Gene Richards in 1977. Raines was caught stealing for the first time in 1981, after having begun his career with a then major league record 27 consecutive successful stolen bases. Raines was the runner-up for the National League's Rookie of the Year Award in 1981, which was won by Los Angeles Dodgers pitcher Fernando Valenzuela.

Raines' performance dipped in 1982, as he hit .277 with a .353 on-base percentage. At the end of the season, Raines entered treatment for substance abuse, having spent an estimated $40,000 that year on cocaine. To avoid leaving the drug in his locker, Raines carried it in his hip pocket, and slid headfirst when running the bases. He used cocaine before games, in his car, after games, and on some occasions between innings in the clubhouse. Raines would later testify at the Pittsburgh drug trials in September 1985.

In 1983, Raines stole a career high of 90 bases, the second-highest total in franchise history, and scored 133 runs, a franchise record. He was named Expos Player of the Year in 1983, 1985, and 1986. In each season from 1981 to 1986, Raines stole at least 70 bases. He had a career-high .334 batting average in 1986, winning the National League Batting Championship. Raines maintained a consistently high on-base percentage during this period and a rising slugging percentage, reaching a career peak of .429 in 1987. Although he never won a Gold Glove Award, Raines was an excellent defensive player who led the National League with 21 assists in 1983 and, with 4 double plays, tied for the league lead in double plays by an outfielder in 1985.

Raines became a free agent on November 12, 1986, but in spite of his league-leading play no team made a serious attempt to sign him (in a period when Major League Baseball owners colluded to keep salaries down). On May 1, 1987, hours after being permitted to negotiate again with Montreal, Raines signed a new deal with the Expos for $5 million over three years and a $900,000 signing bonus. In his first game back, on May 2, facing the Mets, although Raines had not participated in spring training or any other competitive preparation for the season, he hit the first pitch he saw off the right-field wall for a triple. Raines finished the game with four hits in five at-bats, three runs, one walk, a stolen base, and a game-winning grand slam in the 10th inning. Even without having played in April, Raines led the Expos in runs, walks, times on base, runs created, and stolen bases, in addition to batting average, on-base percentage, and slugging percentage. He also garnered MVP honors in the All-Star Game as he delivered a game-winning triple in the 13th inning. Raines would, in 1992, be one of dozens of players retroactively awarded collusion damages, receiving over $865,000.

The Expos traded Raines to the Chicago White Sox on December 20, 1990, along with Jeff Carter and a player to be named later (PTBNL), later identified as Mario Brito, in exchange for Iván Calderón and Barry Jones. Raines later admitted he left Montreal because he wanted to win a World Series and did not believe the Expos "had what it took".

In his first season in the American League, Raines hit for a .268 average but with a .359 on-base percentage; he was second on the team in runs scored as the White Sox finished the season in second place in the American League Western Division. His average improved in 1992 to .294 with a .380 on-base percentage. In 1993, despite missing nearly six weeks in April and May due to a torn ligament in his thumb he sustained while stealing a base, he managed to hit .306 with 16 home runs as the White Sox won the American League Western Division title. In the 1993 American League Championship Series against the Toronto Blue Jays, Raines posted a .444 batting average and scored five runs in a losing cause.