Cubs starter Edwin Jackson said he was thinking about things he shouldn't have been during Chicago's 6-2 loss Thursday to the Milwaukee Brewers.

For now, he doesn't have to ponder being pulled from the rotation.

Jackson lasted 4 2-3 innings and allowed five runs before being lifted for Jacob Turner, who pitched 2 1-3 scoreless innings in his Cubs debut. Jackson has lost six of his last seven decisions and his ERA has risen to 5.74.

Cubs manager Rick Renteria was asked if Jackson (6-12) might lose a start or two to give Turner or other young pitchers a chance.

"Not necessarily," Renteria said. "I don't think that's anything that, quite frankly, is in the forefront of what the organization's thinking."

Renteria did announce that Dan Straily will be summoned from Triple-A Iowa to start Saturday against the New York Mets in hopes of giving Cubs starters extra rest during a stretch of 33 games in 34 days.

When the Cubs signed Jackson to a four-year contract before last season they were hoping the veteran right-hander would eat innings and provide some stability in the rotation. That hasn't happened, and Thursday's start was Jackson's sixth out of 25 where he threw fewer than five innings.

But if he's worried that means he'll lose some turns in the rotation, Jackson isn't showing it.

"At this point you just have to try to worry about the things you control, like I stress all the time," Jackson said. "And that's just worrying about yourself rather than worrying about doing the things you can do once you have the ball."

His opponent did a better job of that.

Mike Fiers (2-1) struck out a career-high 14 in six scoreless innings and walked only one in his second start this season. Fiers and three Brewers relievers combined for 16 strikeouts, but the Milwaukee starter set the tone.

"You could see it right off with him, the first couple of innings," Brewers manager Ron Roenicke said. "You see how guys are swinging at his fastball and when you see they're late on the fastball, you know everything is going to be working."

Khris Davis and Mark Reynolds homered to support Fiers and the Brewers, who are 2 1-2 games ahead of Pittsburgh and St. Louis in the NL Central.

"Personally, it was a great outing, a lot of strikeouts, but the big thing is getting the win," Fiers said.