The Blue Jays launched five homers while Alek Manoah allowed one hit over seven innings to help Toronto close within one game of the wild card-leading New York Yankees.
Toronto began the day tied with Seattle, one game behind Boston for the second wild-card spot.
George Springer, Teoscar Hernández, Bo Bichette and Danny Jansen all went deep for Toronto. The Blue Jays lead the majors with a franchise-record 258 home runs, topping the 257 they hit in 2010.
Baltimore has allowed a big league-leading 254 home runs.
Guerrero grimaced rounding first base on a double in the sixth inning and was checked by trainers but remained in the game. He flied out to end the eighth and was replaced at first base by Cavan Biggio in the ninth.
Trey Mancini doubled to begin the second and scored on Ryan McKenna’s RBI groundout but that was all for the Orioles against Manoah. Nick Ciuffo walked to begin the third and Manoah hit Austin Hays to open the fourth, but neither runner advanced.
Manoah (9-2) retired the final 12 batters he faced and struck out 10. The rookie has a 1.69 ERA in winning his past four starts — his streak includes two wins over Tampa Bay, the AL’s best team.
Springer had four hits and scored twice. Santiago Espinal had three hits and an RBI as Toronto collected 14 hits, the 71st time this season they’ve had 10 or more.
With his 450-foot drive off John Means (6-9) in the first, Guerrero closed within one of Kansas City’s Salvador Perez for the major league lead.
Hernández hit a solo shot off Means in the first, his 32nd, and Springer hit a three-run homer off Means in the second, his 20th. Springer is among seven Toronto players to hit 20 or more home runs this season, joining Guerrero, Hernández, Marcus Semien, Bichette, Randal Grichuk and Lourdes Gurriel Jr.
Bichette hit a first-pitch homer off Konner Wade to begin the fifth, his 29th, and Jansen added a two-run drive later in the inning, his 11th.
Toronto became the fourth AL East team to reach 90 wins, making this the first division since three-division play started in 1994 with four 90-win teams. It’s only the second since division play began in 1969 that it’s happened — the 1978 AL East also had four 90-win teams with New York, Boston, Milwaukee and Baltimore.
Means allowed seven runs and seven hits in three innings.
The game was delayed for several minutes after home plate umpire Chris Guccione left the field to receive medical attention following the top of the third inning. Guccione was eventually replaced by second base umpire Chris Conroy. Crew chief Mark Wegner remained at first base with Alan Porter at third.
Gurriel (right hand) returned to the lineup at DH after sitting out the past two games. Gurriel needed stitches to close a cut on his hand after being spiked by Grichuk on a play in the outfield on Sept. 23.
Blue Jays LHP Hyun Jin Ryu (13-10, 4.39) faces Orioles LHP Bruce Zimmermann (4-4, 4.66) in Sunday’s series finale. Ryu is 3-1 with a 5.40 ERA in five starts against Baltimore this season.