Detroit acquired Montero from Atlanta on Wednesday in exchange for infielder Jim Jarvis.

Montero will join his third team of the season after logging a 5.40 ERA and 1.38 WHIP across 38.1 innings between Atlanta and Houston. He'll likely fill a middle-relief role for Detroit.

Santillan picked up the save in Wednesday's 5-2 win over the Dodgers, striking out one in a clean ninth inning.

Closer Emilio Pagan likely wasn't available after working four of the past five days for the Reds, which created the opportunity for Santillan to nab his third save of the season. Santillan owns a 1.96 ERA, 1.00 WHIP and 28:8 K:BB over 23 innings since the start of June, and he remains firmly in the high-leverage mix with 22 holds on the year.

The Mariners optioned Kowar to Triple-A Tacoma on Wednesday.

The Mariners had to make room in their bullpen after acquiring Caleb Ferguson from Pittsburgh on Wednesday, and Kowar will officially end up as the roster casualty. The 28-year-old righty pitched three scoreless innings after being recalled from Triple-A on Thursday, lowering his big-league ERA to 1.54 through 11.2 frames this season.

Vasil (5-3) earned the win Wednesday over the Phillies, allowing three hits while striking out three over four scoreless innings.

Vasil worked as a bulk reliever and managed to keep a high-powered Phillies offense at bay before the White Sox rallied for seven runs in the seventh inning, en route to a 9-3 victory. The 25-year-old Vasil has been excellent of late, posting a 0.61 ERA over his last seven appearances (14.2 innings). Overall, his ERA sits at an impressive 2.35 with a 1.22 WHIP and 51:36 K:BB across 69 innings in his rookie campaign.

Allard didn't factor into the decision Wednesday against the Rockies, allowing one hit and no walks in 3.1 scoreless innings. He struck out five.

It was an impressive showing in limited action by Allard, who set a season-high in strikeouts Wednesday. The southpaw held the Rockies to a lone single, and he managed to register seven whiffs despite firing just 42 pitches. Through his first 44.2 innings, Allard has a 2.62 ERA, 1.28 WHIP and 28:10 K:BB. If the Guardians need to throw another bullpen game, Allard's next turn in the rotation lines up for next week in Queens against the Mets.

Wentz didn't factor into the decision Wednesday against the Royals, allowing just one hit and three walks over 6.2 scoreless innings. He struck out seven.

Making just his third start of the season, Wentz was stellar, holding the Royals to just one hit -- a single by Maikel Garcia to lead off the game. The 27-year-old left-hander has allowed just four runs (three earned) across 15 innings in his first three starts this year. Wentz has pitched for three teams this season (Atlanta, Minnesota and Pittsburgh) primarily in relief, posting a 5.02 ERA with a 1.44 WHIP and 49:26 K:BB across 52 innings. Wentz has certainly pitched well enough to earn an extended look in Atlanta's rotation, especially given how many starters the team currently has on the IL. He'd currently line up to face the Brewers at home in his next outing.

The Cardinals traded Helsley to the Mets on Wednesday in exchange for Jesus Baez, Nate Dohm and Frank Elissalt, Jeff Passan of ESPN.com reports.

After making a move for Tyler Rogers earlier in the day, the Mets will bring in another quality high-leverage arm in Helsley, who currently boasts a 3.00 ERA through 36 innings and has notched 21 saves this season. With Edwin Diaz already firmly established as the Mets' closer, Helsley will likely join Rogers in working as a setup man in Queens.

The Twins traded Duran to the Phillies on Wednesday in exchange for Eduardo Tait and Mick Abel, Bob Nightengale of USA Today reports.

The Phillies make a huge addition to their bullpen by acquiring Duran, who owns a 2.01 ERA and 1.18 WHIP alongside a 53:18 K:BB through 49.1 innings and has collected 16 saves so far this year. The 27-year-old flamethrower will most likely take over as Philadelphia's primary closer, moving Matt Strahm and Orion Kerkering into setup roles.

The Rangers placed Webb on the 15-day injured list Wednesday, retroactive to Tuesday, due to back spasms.

Webb may have started feeling symptoms during his last outing Monday against the Angels, when he allowed one run on two hits while striking out four across 1.2 innings. He'll undergo further testing to determine the severity of the injury and an estimated schedule for a return, but his absence will require the Rangers to lean more on Cole Winn and Caleb Boushley for relief work. The Rangers recalled Luis Curvelo from Triple-A Round Rock in a corresponding move.

The Rangers recalled Curvelo from Triple-A Round Rock on Wednesday, Daniel Alvarez-Montes of ElExtraBase.com reports.

Curvelo spent time on the Rangers' taxi squad in early June but never received a spot on the 26-man roster. He'll officially join Texas' bullpen this time, however, after logging a 3.26 ERA and 1.28 WHIP with 40 strikeouts through 38.2 innings at Round Rock. The 24-year-old righty will be making his MLB debut whenever he gets into a game.