Even with 2½ weeks left in the regular season, the Chicago Cubs' pitching rotation remains ever-changing.
They will go so far Thursday to give a pennant-race start to a pitcher making his major-league debut.
An old stalwart, Jon Lester, added to the intrigue Wednesday night by running his pitch count up early but then staying in the game through 6 innings as the Cubs defeated the New York Mets 17-5 at Wrigley Field. The Cubs (79-66) are 2½ games ahead of second-place Milwaukee in the National League Central and 3 ahead of St. Louis.
It was Lester's third start since coming off the disabled list, and he battled command issues early before breezing through his final 3 innings.
The rotation roulette will continue in the series finale when the Cubs give the ball to right-hander Jen-Ho Tseng, whom they selected from Class AAA Iowa on Wednesday after an outstanding season that led to him being named the Cubs' minor-league pitcher of the year.
"I just sat down with him in my office, and I said, 'I guess you're in town to accept an award tomorrow as being the minor-league pitcher of the year,' " manager Joe Maddon said. "He just looked at me. And I said, 'How about if you start tomorrow night's game instead?'
"He didn't even blanch. It's like, 'My God.' Actually his interpreter was more taken by the whole situation than Jen-Ho was.
"I heard nothing but good things about this kid. I've watched the video. We think right now, in order to get us all set up pitching wise, it was the right thing to do."
Between Iowa and Class AA Tennessee, the 22-year-old Tseng was 13-4 with a 2.54 ERA. With that move, the Cubs put swingman Mike Montgomery back in the bullpen. Montgomery was supposed to start Thursday's game, but he moves back into a role in which the Cubs feel comfortable using him.
Left-handed reliever Justin Wilson has struggled since coming over in a trade with Detroit, leaving Brian Duensing as the only dependable lefty in the pen.
"First of all, we needed some more help in the bullpen," Maddon said. "And Monty's so versatile and he was amenable, and we talked about it.
"There's other things going on that we think is going to be better for us to put Monty back out there. If Jen-Ho was not available, this would not be happening. Guys like him that much. He's been in Arizona throwing. Minor-league pitcher of the year. So there's a lot to like about this guy."
Lester (11-7) said his issues are all about command.
"If I could take the last 3 (innings) from the last two games, it would be a lot better," he said. "For whatever reason, I don't know, just not real crisp early on right now. Figure it out. Game of adjustments. We've got to make some."
The Cubs scored a pair of runs in the first inning against Matt Harvey. They chased him in the fourth with 3 runs and added 4 more in the seventh on a solo homer by Javier Baez and a 3-run shot by Albert Almora Jr.
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