The Houston Astros have acquired veteran left-handed starter Francisco Liriano in a trade with the Toronto Blue Jays, the team announced Monday.

The Astros are getting Liriano in exchange for outfielders Norichika Aoki and Teoscar Hernandez. He is expected to join the team Tuesday in Houston.

Liriano has struggled in 2017, posting a 5.88 ERA in 18 starts for Toronto, but could be a useful arm in the bullpen for the American League West-leading Astros. He has held lefties to a .615 OPS this season with only one walk.

Entering play Monday, the Astros' rotation had the best ERA in the American League at 3.97, but has been riddled with injuries.

After a nearly two-month layoff, Houston ace Dallas Keuchel made his return Friday, lasting just three innings against the Tigers.

The Astros also got Collin McHugh back recently, making his 2017 debut on July 22 after dealing with an elbow injury.

Toronto acquired Liriano from the Pirates at the trade deadline last season, and he helped the team reach the postseason with a 2.92 ERA in 10 games for the Blue Jays.

Liriano is a free agent after this season.