Then, if the Rockies want to go back to a five-man rotation, they can start Pomeranz on Friday. The four-man experiment carries with it a 75-pitch limit, because the Rockies are pushing for their starters to be aggressive in the strike zone early -- something White didn't do in any of his last three starts.White has posted a 9.58 ERA with 18 hits and 10 walks in 10 1/3 innings in his last three starts. White and Pomeranz were the key pitchers obtained from the Indians when the Rockies dealt former All-Star right-hander Ubaldo Jimenez to Cleveland last year. White gave up four runs, six hits and four walks in just 2 2/3 innings of Sunday night's 4-2 loss to the Rangers. Alternately, White was reaching two strikes, then missing the strike zone, or he was falling behind and having to put the ball over the heart of the plate. "The consistency, that's where we're struggling and that's where we have to get better," said Tracy, who also said White needs to do a better job of making his secondary pitches appear to be strikes before diving out of the zone. The key question is whether the Rockies deem Pomeranz, the fifth overall choice in the 2010 First-Year Player Draft, ready for the Majors. Sunday's start, a win over Tacoma, followed a start against Salt Lake City in which Pomeranz threw six no-hit innings with eight strikeouts and three walks. Before that, he usually kept his run total low, but allowed either high hit or walk totals. Those lead to high pitch counts in early innings that could spell trouble in the Majors. Reports say Pomeranz's velocity, which dropped when he slipped into a sidearm motion, is creeping back into the 90s. Tracy praised Pomeranz's recent work and said he is "making progress." Whether it's enough progress for him to return now is a matter for the Rockies' brass to decide. Pomeranz appeared to fall into bad habits last year, when he was idle for 17 days because of red tape involving the trade and then underwent an emergency appendectomy shortly after joining the Rockies' Double-A team in Tulsa. Pomeranz was 0-2 with a 5.40 ERA in five Major League starts before the Rockies decided to send him down to clean up his motion. "[Sunday's] outing, was it a competitive outing? Yes it was," Tracy said. "Like I said in relation to Alex White, he's 22 years old. So is he making strides? Yes. His velocity is coming up a little bit. He's had an opportunity to work on his mechanics. "For a kid that's 22 years old, fresh out of college, so you get some back and forth. You get brilliant, you get middle of the road, you might get a bad one, then you'll get a really good one. Over time, you'll get to a point where you get really consistent and with the stuff that he has and the capability he has, you'll have a very good pitcher." On Monday, the Rockies called up right-handed relief pitcher Zach Putnam from Colorado Springs. Putnam, 1-2 with a 4.94 ERA and 11 saves in 25 Triple-A relief appearances, has been called up twice and pitched one scoreless Major League inning.
Thomas Harding is a reporter for MLB.com. Read his blog, Hardball in the Rockies, and follow him on Twitter @harding_at_mlb. This story was not subject to the approval of Major League Baseball or its clubs.