Detroit Tigers left-hander Sean Guenther will serve as the team's opener ahead of right-hander Keider Montero for Monday's series opener against the St. Louis Cardinals at Busch Stadium, according to the Detroit News' Chris McCosky. This will be the first career MLB start for Guenther, who should be avoided as a fantasy streamer. The 29-year-old southpaw currently has a 2.25 ERA and 1.00 WHIP with six strikeouts and three walks in six relief outings for Detroit over eight innings pitched. He has not gone beyond two inning pitched in any of his six relief appearances for the Tigers this year, so fantasy managers shouldn't expect him to go very deep at all against St. Louis in this one. This will be Montero's second straight outing in a bulk-relief role. He gave up three earned runs in 3 1/3 innings in the same role last week against the Boston Red Sox.

The Detroit Tigers claimed relief pitcher Sean Guenther off waivers from the Miami Marlins on Wednesday, according to a tweet from the team's public relations Twitter account. The left-hander, who had Tommy John surgery in April, appeared in 14 games for the Marlins in 2021, logging a 9.30 ERA and a 4.10 FIP in 20.1 innings to go along with 15 strikeouts and 10 walks. He turned in a 4.76 ERA, a 2.83 FIP, 28 strikeouts, and four walks in 22.2 innings with Miami's Triple-A affiliate during the same season. Per the tweet from the team's public relations Twitter account announcing the move, Guenther "remains on the 60-day injured list."