Jennings ends his season with a 6-9 mark and 5.02 ERA.
It's a real shock to the Rockies because Jennings had been a very durable starter.
"I think the reason he's been durable," Hurdle said. "When you talk about durability with a pitcher, you talk about his shoulder and his elbow and those kinds of things and this is something that happened running the bases. He tried to make a baseball play and break up a double play. It's unfortunate, but he plays the game hard. This is one of the byproducts of playing the game hard and that being said, it was tough initially to swallow, but again one of the things we've been very focused upon is moving forward.
"Once he sees the specialist and they draw up a plan for him, he'll follow it and he'll continue to workout. We'll move forward, and we'll look at Acevedo to fill the spot on Monday. [Acevedo's] going to throw a bullpen [session] tomorrow. We need to see where he is because he did have the high-ankle sprain from Tuesday night. If he's able to, I think we can pencil him in Monday.
As we move forward, we'll probably bring a pitcher up tomorrow. We'll get a guy to take Jennings' spot and put him in the bullpen."
Anderson Machado, the infielder that the Rockies claimed off waivers from the Cincinnati Reds on Wednesday, arrived in Pittsburgh before the end of Thursday night's game.
"I just found out Wednesday before I went to the ballpark," Machado said. "I received a call and I heard the Colorado Rockies picked me on waivers. I feel a little sad, but I know I will have more opportunities to play here. I'm glad Colorado picked me because I didn't have a chance to play in Cincinnati. I'm glad for [Felipe Lopez] because he's doing a really good job with the Reds. Here I will have more opportunities I think."
Machado appeared in two games for the Reds this season, both as a pinch-hitter, and was 0-for-2. He began the year on the 15-day disabled list, following offseason surgery to repair a torn medial collateral ligament and torn meniscus in his left knee. He played in 21 games during a rehab assignment with Triple-A Louisville and hit .138 with six RBIs.
Colorado was concerned about Machado's surgically repaired left knee.
"We just got a call maybe an hour ago from Dr. Thomas Noonan," Hurdle said. "We are going to fly Machado back here and get him activated tomorrow. I don't think he's going to get until midnight.
"He's got some rehab that he's got to continue to do, but he's healthy. He just can get a lot stronger. He was looked at here, but the guy wasn't comfortable with what he saw and he wouldn't sign off on it. He said he would only co-sign off on it after Noonan saw it. So we sent him to Noonan and he deemed him playable, but there's a lot of room for him to reacquire some strength."
Hurdle said he plans to see if Machado can handle the shortstop spot.
"That's good, I was supposed to fight for the job with Cincinnati this year," Machado explained. "But I got hurt playing winter ball -- I broke my knee -- and thank God I feel better now. I'm just coming here to Colorado and I'm just going to play hard and try to do my best."
Machado still has some concerns about his knee.
"I feel fine," Machado offered. "It doesn't hurt -- I have to keep working hard to get my leg stronger and try to get my speed back. That's one of my skills that I have to bring back. I'm just going to keep working and try to get it back."
The Rockies face the Pirates in Game 3 of a four-game series on Saturday. Colorado will send right-hander Byung-Hyung Kim to the hill to face Pittsburgh's Dave Williams.