2015 Toronto Blue Jays season

[5] Toronto acquired Donaldson in a five–player trade, sending Brett Lawrie, Kendall Graveman, Sean Nolin, and Franklin Barreto to Oakland Athletics.

Discussions ended when it was reported that Baltimore was seeking a compensation package of 3 first-round selections (Jeff Hoffman, Max Pentecost, and Mitch Nay).

[34] Prior to the official start of spring training, Michael Saunders tore the meniscus in his left knee on February 26 and was initially expected to go on the disabled list until the All-Star break.

[49] Attending spring training for the first time, both Roberto Osuna and Miguel Castro impressed Blue Jays management with their abilities, and both earned positions in the bullpen on the Opening Day roster.

[61] Drew Hutchison, who became the youngest opening day starter in Blue Jays history,[63] pitched six innings giving up three hits, including a solo home run to Brett Gardner.

[69] Aaron Sanchez, another of Toronto's top prospects, made his first career MLB start against Ubaldo Jiménez the following night, but would last just 31⁄3 innings and yield 3 earned runs.

Beginning a 10-game road trip, the Blue Jays travelled to Tropicana Field in Tampa Bay to take on the Rays and were swept, losing 12–3,[82] 4–2,[83] and 5–1 in the three-game set.

Before the game, top prospect Daniel Norris was optioned back to Triple-A Buffalo, and Marco Estrada was announced as his replacement in the starting rotation.

[93] Following the loss, the Blue Jays demoted Miguel Castro and Scott Copeland, and recalled Chad Jenkins and Steve Delabar from Buffalo to replace them.

[121] Aided by another strong starting pitching performance from Drew Hutchison, the Blue Jays earned their first four-game winning streak of 2015 by beating the Astros 7–2 in the second game of the series.

Chris Colabello hit a go-ahead home run in the twelfth and Steve Delabar earned his first save of the season as the Blue Jays took 2 of 3 from the Rays.

[144][145] The Blue Jays opened July with a win over the Red Sox on Canada Day, 11–2, backed by 5 home runs and another strong start by Mark Buehrle.

[158] In the rubber match, the Jays came back from being down 7–0, scoring 8 runs in the sixth inning to take the lead; however, poor pitching would again befall them, losing 11–10, and ending the unofficial first half of the season with a 45–46 record.

[163] Toronto began a 6-game trip to the west coast in Oakland, taking on the Athletics for the first time since the trade that made Josh Donaldson a Blue Jay.

[169] In the early hours of July 28, Toronto pulled off a blockbuster trade with Colorado, sending José Reyes, Miguel Castro, Jeff Hoffman, and Jesus Tinoco to the Rockies in exchange for Troy Tulowitzki and LaTroy Hawkins.

Royals starter Edinson Vólquez intentionally hit Josh Donaldson with a pitch in the first inning, and both benches were warned by home plate umpire Jim Wolf.

Newly acquired ace David Price made his first start for Toronto and lead them to a 5–1 victory, pitching 8 innings and striking out 11, which tied a franchise record for strikeouts in a Blue Jays debut.

[179] The Blue Jays would take sole possession of the second Wild Card spot with a 3–1 win that night, aided by another strong start from Marco Estrada.

[190] In the finale, Athletics starter Sonny Gray was scratched due to back spasms, and former Blue Jay Jesse Chavez started in his place.

Aaron Sanchez would give up a three-run home run to Carlos Beltrán, and New York would hang on to beat the Jays 4–3, ending their streak, and knocking Toronto out of first place in the AL East.

The matchup saw the two leading American League MVP hopefuls, Angels center fielder Mike Trout and Blue Jays third baseman Josh Donaldson, go head-to-head.

[203] Toronto's offence set new franchise records for hits and runs scored in a three-game series, with 48 and 36 respectively,[204] and moved back into first place in the AL East by a half game.

[214] The Blue Jays opened September with a 5–3 win over Cleveland, after Ryan Goins hit a walk-off two-run home run in the tenth inning.

Mark Buehrle, who had been pushed back two days due to fatigue, lasted only 31⁄3 innings as the Blue Jays fell to the Red Sox 11–4 in game 1, and saw their lead over New York shrink to just a half-game.

Mark Buehrle made his return to the rotation after leaving to get a cortisone shot in his left shoulder, but the Blue Jays would lose the first game of the series, 3–2.

[232] The win gave Toronto a 41⁄2-game lead in their division, however they would give that game back the following day, losing 7–6 to Boston, coupled with the Yankees defeating the Mets.

The Blue Jays led the game 4–2, heading into the ninth inning, however Roberto Osuna and Aaron Sanchez would combine to give up 5 runs to the Red Sox.

[239] The Blue Jays would complete the sweep, winning the final game of the series 5–4 thanks to Josh Donaldson's franchise record third walk-off home run of the season.

[245][246] Still in contention for the best record and home field advantage throughout the playoffs, the Blue Jays played their final three regular season games in Tampa Bay against the Rays.

Rougned Odor, who was at third base, scored the go-ahead run on the play, though initially home plate umpire Dale Scott rules the ball dead.