Jorge Mateo injury update: Orioles infielder undergoes season-ending elbow surgery after June collision

If the Baltimore Orioles are to overcome the New York Yankees and claim their second consecutive American League East title, they'll have to do it without veteran infielder Jorge Mateo . Mateo, who hadn't played since July 23 after suffering an elbow injury in a collision with a teammate , underwent season-ending surgery to both install an internal brace and to repair his flexor tendon in his non-throwing arm.

Mateo, 29, was in the midst of the best offensive season of his big-league career. In 68 games prior to the injury, he batted .229/.267/.401 (91 OPS+) with five home runs and 13 stolen bases (on 15 attempts). His contributions had been worth an estimated 0.8 Wins Above Replacement, according to Baseball Reference's calculations.

In the month-plus since Mateo went down, the Orioles have by and large turned over the keystone to young Jackson Holliday , the top prospect in all of baseball entering the year. Holliday has performed better since returning to the majors than in his first go-around, albeit perhaps not up to the expectations summoned by his name and pedigree: in 26 games, he's batted .211/.268/.422 with five home runs.

The Orioles enter Thursday with a 77-57 record, putting them a game back of the Yankees in pursuit of the AL East crown. Baltimore will wrap up a potential World Series preview against the Los Angeles Dodgers on Thursday before beginning a stretch that will see them play several non-contenders in a row -- the Colorado Rockies , Chicago White Sox , and Tampa Bay Rays . The Orioles can also rest easy knowing they'll play three more games against the Yankees, in New York, during the final week.

Baltimore possesses a 6-4 advantage in head-to-head games with the Yankees. MLB did away with tiebreaker games as part of the expanded postseason format, meaning that the winner of the head-to-head series has a built-in advantage in the event of a tie.