PHOENIX -- The Diamondbacks will let another rookie stake his claim for a spot in what appears to be a wide-open 2015 starting rotation in the final two weeks of the season.
Left-hander Andrew Chafin will start against San Francisco ace Madison Bumgarner on Wednesday afternoon, manager Kirk Gibson said, and the only surprise seemed to be in the timing of the announcement.
Chafin threw 15 scoreless innings in Triple-A Reno's run to the Pacific Coast League championship series, and giving him another look after a Monday recall seemed only a matter of time.
At the same time, right-hander Chase Anderson will be shut down after his start Friday in Colorado, Gibson said. Anderson, who leads NL rookies with nine victories, has thrown a career-high 148 1/3 innings this season, including his time at Double-A Mobile before his major league debut May 11.
"We obviously wanted to get (Chafin) to pitch," Gibson said.
"It gives us a chance to watch him. More so, it's an opportunity for him to try to build on the momentum he has now. When they come up, it's a different game for sure. We just want to see him compete. Hopefully he'll benefit as he moves into the offseason."
Chafin, 24, made a strong impression in his only other D-backs appearance, pitching five scoreless innings in the second game of a doubleheader against Cleveland on Aug. 13. He gave up three singles and two walks but did not get a decision in a 1-0, 12-inning victory.
Chafin, 9-7 with 4.08 ERA at Reno and Double-A Mobile this season, will take Randall Delgado's spot in the final two turns in the rotation, with another start coming Tuesday in Minnesota.
"Do we move Chafin to the bullpen?" Gibson said. "We didn't want to do that. He's throwing the ball really well as a starter. He's been starting for a while. We didn't feel it would be good for him to put him at the bullpen at this point."
So Chafin will join the crowd competing for future rotation spots behind Wade Miley. That group includes Anderson, Josh Collmenter, Trevor Cahill, Vidal Nuno and perhaps Delgado in camp next spring, although the D-backs also will be in the market for rotation help in the offseason. The D-backs hope to get Patrick Corbin and Bronson Arroyo back from Tommy John surgeries in May and July, respectively.
Ender Inciarte led off the first inning with a hit for the fifth straight game. He scored the first two times but has been stranded the last three.
1.01 -- Josh Collmenter's ERA over his last five starts, when he has given up four earned runs.
*Josh Collmenter made his fifth straight quality start, although it did not result in a win because the D-backs could not solve Jake Peavy. Collmenter was touched for two runs, one on home run by personal nemesis Buster Posey, who has the same effect on Collmenter as Paul Goldschmidt has on Tim Lincecum. Posey is 11-for-18 with three homers and eight RBI in the career matchup. "Maybe the ball looks like a beach ball to him, I am not sure," Collmenter said. "Up and down, soft and hard, it doesn't matter, he seems to get the bat on it." Posey said the kind of thing Goldschmidt says when asked about his work against Lincecum (15-of-28, seven homers): "Who knows? It's just one of those baseball oddities, I guess."
*Jake Lamb, who not played since Friday because of a sore quadriceps, was used as a pinch-hitter in the eighth, striking out.
*Giants shortstop Brandon Crawford made a rally-killing play on Mark Trumbo's grounder up the middle to open the ninth inning. Crawford fielded the ball behind second base and threw across his body to nip Trumbo for the first out of the inning.
*Brett Jackson made his first start since Oct. 3, 2012, when he opened in right field while David Peralta nurses a back injury and Cody Ross was given a day off. He was 0-for-2 with a walk. Jackson was a first-round pick of the Cubs in the 2009 draft, and D-backs coaches Dave McKay and Alan Trammell worked with him in Chicago. "There were a lot of expectations put on that kid when he came up here," Kirk Gibson said. "Trying to get him by those and encourage him to get a different place mentally. Make some physical adjustments."
It did not take Jake Peavy long to turn his focus to his next start against the Dodgers on Monday after his 2-1 victory over the D-backs. "I'm not going to lie to you," Peavy said. "I was just in the shower and I was thinking about (Dodgers leadoff hitter) Dee Gordon to be honest with you. Isn't that crazy? Isn't that unbelievable? I was taking a shower going, how do we get Dee Gordon? My mind will be all L.A. through the weekend. I'll be getting ready for that start. I'll do all I can do, because that is going to be a must win."
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