MINNEAPOLIS -- For all the concerns that have been voiced about the Twins’ bullpen to open the second half, Minnesota’s relief unit has quietly settled into a strong groove over the past week.

The Twins’ lineup was no match for White Sox starter Lucas Giolito, who held the normally potent Bomba Squad to only three hits in a shutout, but the bullpen more than held its own opposite the 25-year-old right-hander, as Ryne Harper, Sam Dyson, Tyler Duffey and Trevor May combined for four scoreless innings after starter Jake Odorizzi gave up four runs (three earned) in five innings in the Twins’ 4-0 loss on Wednesday at Target Field.

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Giolito was masterful as he went the distance, striking out 12 without issuing a walk and allowing only one Twins runner to advance beyond second base on a one-out double by Jonathan Schoop in the eighth inning. His effort marked the first shutout thrown against the Twins since Jake Arrieta did so for the Cubs on June 21, 2015.

“He’s a tough customer, and he was on his game,” Twins manager Rocco Baldelli said. “He pounded the strike zone, but he also has elite stuff, too. He made it tough for us from the get-go. We weren’t really able to get much going off of him. He didn’t bite himself in the foot in any way. He kept bringing it to us, and today we just didn’t have the answer for him.”

But in the bigger picture, the bullpen continuing to find a groove, is likely a more significant development than one bad afternoon at the plate against a young budding ace, and the relief corps certainly provided a bright spot in the series defeat to the White Sox.

Lost in Tuesday’s offensive fireworks and Wednesday’s lack thereof was the fact that the bullpen combined to allow only one run in 8 1/3 innings in the three-game series. If you include the final three games of the series against the Rangers, that becomes two runs in the past 20 1/3 frames for a relief corps that looks to have been stabilized by the additions of Sergio Romo and Dyson at the Trade Deadline.

"Everybody feels comfortable in there,” said Harper, who escaped a sixth-inning jam. “Everybody's got their roles. Everybody's good to do anything. It's a long season, there's always ups and downs. … I think we're meshing well going down the stretch."

It’s all the more of a welcome turnaround given that the Twins’ relievers had entered the game with a 4.61 ERA since the All-Star break and a Major League-leading 12 blown saves in the second half.

Much of that recent success has come from three converted starters who have blossomed into their new roles over the past several seasons: Duffey, May and Zack Littell.

Duffey has not been charged with a run in his past 12 appearances, a stretch dating back to July 28 during which he has allowed only three hits in 9 2/3 innings, with 15 strikeouts and four walks.

After gaining leverage experience in late-game situations earlier in the season, Duffey has taken well to a new “fireman” sort of role in the bullpen, entering with traffic on the basepaths in high-leverage situations, often to clean up a starting pitcher’s final inning.

"I think the reason he's having that success is because we had him, earlier in the year, in that seventh and eighth,” pitching coach Wes Johnson said. “But you've seen Duffey get comfortable with the plan, understanding how to attack, getting really acclimated to his throwing plan and how we're using him.”

Though he was optioned to Triple-A Rochester on Monday due to the composition of the roster, Littell figures to be an important part of the equation once he returns, as the 23-year-old has allowed only two runs in 17 games since he was converted to full-time relief in mid-June.

And May has continued to make clear progress in his early-season struggles with walks and falling behind in counts, as he did not issue a free pass for his third straight outing on Wednesday despite allowing a single -- the first hit he has given up in nearly two weeks.

“I want to finish this year out by really, really mastering where I want to throw the ball and where I'm most effective,” May said. “That's what I want to do, so I use this as, 'Go out and lock that in.'”

Dyson’s return from injury on Aug. 13 and Romo’s continued success since his acquisition from the Marlins have afforded the Twins the opportunity to use Duffey and May in different situations. When they pair that with the progress that both pitchers have made individually over the course of the season, it could be a recipe for things to click during this upcoming crucial stretch of a pennant chase.

“It does help when you've got two veteran guys to come in like Sam Dyson and obviously [Romo],” Johnson said. “It allows Trevor and Tyler to do some things different, and you put all those pieces in a funnel, and what comes out is the little bit of success that we're having in the 'pen right now."