Right-hander Jen-Ho Tseng is a fourth-year Cubs minor leaguer who started the season at Class AA Tennessee and has yet to earn a big-league spring training assignment.
On Thursday he makes his big-league debut as the Cubs’ starting pitcher in the middle of a pennant race in the middle of September, against the Mets.
The Cubs announced the surprise move Wednesday after stashing Tseng in Arizona to keep pitching over the past week since his minor-league season ended.
The biggest, immediate impact is that it allows the Cubs to move left-hander Mike Montgomery out of the rotation to bolster a bullpen that has gotten next to nothing from lefty Justin Wilson since trading for him seven weeks ago and that has been without struggling righty Koji Uehara (knee infection) for almost two weeks.
“Sometimes you catch lightning in a bottle and you learn some things, too,” said manager Joe Maddon, who was informed of the decision by the front office. “You never know what happens after that with some young players. Even if it’s not a start that happens afterwards, maybe he’s going to help us in another way; I don’t know.
“I’m keeping a very open mind. I’m actually excited about seeing it. And I trust the people making these decisions.”
Tseng, 22, was named this week as the Cubs’ minor league pitcher of the year – the second time he has earned that distinction (also 2014) – after going 13-4 with a 2.54 ERA in 24 starts at AA and AAA combined (145 1/3 innings).
Maddon recalled that David Price debuted with the 2008 Rays in September and played a big role for the American League pennant winners out of the bullpen through October.
Tseng isn’t the No. 1 overall draft pick and power pitcher that Price was, nor does he project as a front-of-the-rotation starter.
Maddon compared his style to fastball-changeup, command pitcher Kyle Hendricks – with a quicker fastball, closer to the low 90s.
“I’ve heard nothing but good things about this kid,” Maddon said. “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.”
Maddon said the move had less to do with Jake Arrieta’s injured hamstring than providing better options in the bullpen.
The Cubs open a three-game series against second-place St. Louis on Friday.
To make room on the 40-man roster for Tseng, the Cubs designated right-hander Pierce Johnson — the first pitcher drafted by the Cubs under Theo Epstein — for assignment.
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