The Astros purchased the contract of Jankowski -- a 28-year-old, right-handed reliever -- on Monday, one day after optioning reliever Ashur Tolliver to Triple-A. To make room for Jankowski on the 40-man roster, the Astros designated Minor League outfielder Andrew Aplin for assignment.
With long reliever Brad Peacock getting a spot start Monday against the Tigers, the Astros needed a fresh arm. Jankowski, who's been in big league Spring Training the past three years, has appeared in 17 games at Fresno and allowed 13 hits, three earned runs, nine walks and struck out 22 in 19 innings, posting a 1.42 ERA. His fastball-slider combo is what set him apart, Astros manager A.J. Hinch said.
"He has a chance to be effective," Hinch said. "We wanted him to get to the big leagues over the past few transactions, and it hasn't fallen his way. I'm happy for him. There's only one first day. There's a great excitement, especially for him. He's been stagnant in Triple-A, just outperforming that league for a couple of years now. He's got real weapons."
Jankowski, a 34th-round pick in the 2012 Draft, said his parents and mother- and father-in-law made Monday's game, along with his pregnant wife and other relatives. The couple is expecting its first child in the summer. For now, nothing tops getting his first call to the big leagues.
"I've been waiting a pretty long time, and just happy to be here," Jankowski said.
Brian McTaggart has covered the Astros since 2004, and for MLB.com since 2009. Follow @brianmctaggart on Twitter and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.