[7] However, tragedy launched Major League Baseball's 2014–15 off-season when Cardinals rookie right fielder Oscar Taveras was killed in a car accident in the Dominican Republic on October 26, 2014.

[10] Reports confirmed alcohol intoxication on Taveras' part,[11] making it the second alcohol-related fatality of a Cardinals player in a car accident since pitcher Josh Hancock in 2007.

Further, a large decal was posted in his memorial on the wall of the home team bullpen of Busch Stadium along with those of Hancock and Darryl Kile, another pitcher who died during the 2002 season while still active as a player.

[19] The day after the World Series ended, October 30, Mark Ellis, Justin Masterson, Jason Motte, Pat Neshek, and A. J. Pierzynski all filed for free agency.

[25] The Cardinals picked up the 2015 option on starting pitcher John Lackey's contract on October 30, equivalent to the minimum salary of $507,000 ($652,529.1 today), an unusually low number on for a veteran of his achievement level and competitiveness.

The Red Sox inserted a provision in the contract that, in lieu of paying insurance in case he missed any season due to an elbow injury, the club could choose to pick up an option in 2015 for the league minimum salary.

[68] Participating in the first-ever night game Opening Day to commence an MLB season, the Cardinals faced off against the Chicago Cubs on April 5, partners in an historic sports rivalry.

[72] From April 12–19, third baseman Matt Carpenter netted seven consecutive games with at least two hits and one double, tying Ripper Collins for the franchise record he set in 1935.

[79] On April 25, Harris made his major-league debut, substituting for Wainwright in a game against Milwaukee after he suffered an ankle injury, and struck out his first batter, Adam Lind.

[95] Four new members of the St. Louis Cardinals Hall of Fame Museum were announced on May 5, including Curt Flood, Bob Forsch, George Kissell and Ted Simmons.

However, Flood is best known for challenging the reserve clause, which in spite of the United States Supreme Court ruling in MLB's favor, eventually led to free agency.

[116] On June 8, Holliday suffered a right quadriceps strain while attempting to catch a fly ball off the bat of Carlos González during a game against the Colorado Rockies.

[118] In the MLB Draft, the Cardinals selected outfielder Nick Plummer with the 23rd overall and team's number-one pick from Brother Rice High School in Michigan.

[120] Lyons, whom the Cardinals recalled from Memphis to take the place of an injured Lance Lynn on June 13, stopped a winless streak of 13 MLB starts by pitching a 3–2 victory over the Royals.

[130] The Cardinals optioned Lyons back to Memphis to make room on the roster for Lynn,[131] who started the next game against the Marlins, pitching six scoreless innings in a 5–1 victory and series sweep.

Pete Kozma, filling in for Peralta at shortstop, scored on that double had three hits and reached base in four plate appearances,[132] snapping an 0–21 streak that dated back to May 19.

[144] On July 4, the Cardinals defeated the Padres 2–1 as center fielder Tommy Pham, just recalled from Memphis, was influential in helping snap the four-game losing streak.

[155] In the morning of July 12, the Cardinals dropped their second straight game (that had started the night before) to the second place Pirates, after Andrew McCutchen hit a walk off home run off Nick Greenwood in the bottom of the 14th inning.

[163] Matt Holliday's first home run in his return from the disabled list was a grand slam against Carlos Rodon of the Chicago White Sox in an 8–5 win on July 21.

Grichuk hit a two-run home run, and, setup man Kevin Siegrist, filling in for closer Trevor Rosenthal, recorded his fifth save of the season.

[173][174] To help offset the loss of batting production from Holliday's return to the DL, the Cardinals acquired first baseman and outfielder Brandon Moss from the Indians for LHP Rob Kaminsky.

[179] On August 5 against the Reds at Great American Ball Park, Grichuk doubled in the sixth inning and hit the game-winning home run in the top of the 13th for a 4–3 win.

Those rating at or near the top of various categories included Carpenter for "best strike zone judgment" (third), Yadier Molina for both "best hit and run artist" (tied for first) and "best defensive catcher" (first), Trevor Rosenthal for "best reliever" (third), and Mike Matheny for "best manager" (second).

[31] With the Cubs seven games back, the first-place Cardinals visited Wrigley Field on September 18 to start a three-game series, continuing a renewed Cardinals–Cubs rivalry with Chicago being more competitive than in recent years.

Addison Russell hit a fly ball that Heyward caught running and threw home to Molina to tag out Rizzo by two steps, helping preserve a 4–3 win.

The same day, the Cardinals announced Adam Wainwright was cleared to resume baseball activities ahead of schedule after diligently rehabilitating his Achilles tendon rupture throughout the season.

[231] Infielders Other batters Coaches The Cardinals faced off in a best-of-five series against the rival Chicago Cubs in the postseason for the first time since joining the National League in 1892.

John Lackey started Game 1 for the Cardinals, opposing Jon Lester, who had both faced St. Louis in the 2013 World Series as members of the Boston Red Sox.

[297] While carrying out a rehabilitation assignment with the Peoria Chiefs on July 23, RHP Jaime García pitched in a combined no-hitter and 2–0 win against the Clinton LumberKings, a Seattle Mariners affiliate.

Other selections notified the Cardinals of their intention to continue playing college baseball: Kép Brown (10th round), Gio Brusa (23rd), Matt Vierling (30th) and Parker Kelly (34th).