By Bruce Levine–

CHICAGO (CBS) — Pitching in baseball obscurity, right-hander Mike Pelfrey was a minor league hurler for the White Sox when opportunity knocked in late April. Rotation member James Shields went down with a right lat injury, and Pelfrey was summoned from Triple-A.

After a slow start, the 33-year-old Pelfrey has been impressive of late, including Wednesday when he tossed five shutout innings in his team’s 4-1 loss to the Red Sox and their vaunted offense at Guaranteed Rate Field. Pelfrey scattered two hits and two walks while striking out five before the White Sox bullpen blew his 10 lead by allowing four runs in the sixth inning.

Pelfrey has allowed just two earned runs in 16 innings across his past three starts to go along with a 0.81 WHIP in that stretch.

A change in his pitching approach has been key, Pelfrey said, as he’s used breaking balls and cutters away more effectively to hitters.

“My week spot during my whole career has been down and away to right-hand hitters,” Pelfrey said. “I have had trouble commanding that pitch. I always pulled off it a little bit. Working hard in my bullpens, I now feel it is a strength. I feel fine about the progress I have made after getting kicked around at (Triple-A) Charlotte.”

A first-round pick of the Mets in 2005, Pelfrey has struggled since going 15-9 for New York in 2010. He’s since bounced from the Mets to the Twins to the Tigers, who released him in late March with $8 million guaranteed for 2017 before the White Sox scooped him up on a minor league deal.

On Wednesday, manager Rick Renteria said that he had scripted the game for Pelfrey to go just five innings or 80 pitches, which is why he was pulled despite his shutout effort. The statistic Renteria had in mind was that opposing lineups are hitting .556 against Pelfrey the third time through the batting order.

“You just don’t want it to open up and bring in a reliever with men on base,” Renteria said. “All of us want to protect the pen against traffic. You prefer they work in a clean inning. That was basically what we tried to do.”

Pelfrey didn’t fight Renteria’s decision to pull him Wednesday despite working a quick one-two-three fifth inning.

“My job is to give everything I have until they come take the ball,” Pelfrey said. “Obviously he is the boss and makes the decision. We are on the same team. I don ‘t try to talk him out of it. I felt fine. He said that is enough, so it’s enough.”

Bruce Levine covers the Cubs and White Sox for 670 The Score and Follow him on Twitter @MLBBruceLevine.

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