"It's a precaution," Guerra said through translator Carlos Brizuela. "That's why the trainers wanted to just take it slow. They don't want it to get any worse than it is. It should be good in less than two weeks, really."
This campaign has been a breakthrough season for the journeyman Guerra. Claimed off waivers from the White Sox during the offseason, he owns a 2.93 ERA and 3.64 FIP over 17 starts and 107 1/3 innings. Guerra's ERA ranks first among National League rookies and his 2.2 WAR, according to Fangraphs, is tied for third among all rookie pitchers.
"Just precautionary as much as anything, and just give him time, really, to not rush it," Counsell said. "I don't have a timeframe. It could be two weeks. It's still a possibility that it's just a 15-day episode."
Guerra told reporters after Monday's loss that he has no prior history of any elbow injuries. He has not felt any pain on the mound, but has experienced inflammation and swelling. Peralta will take Guerra's place in the rotation on Tuesday, and the Brewers will assess the situation following that start.
Over 13 starts prior to his demotion to Triple-A, Peralta struggled to the tune of a 6.68 ERA and .358 batting average against. For Peralta, his return to Milwaukee represents a fresh chance to start over at the big league level.
"It is a second chance," Peralta said. "I spent almost two months down [in Colorado Springs], and every time you get this opportunity, you have to take advantage. I got the opportunity a few years ago, and I just took advantage, stayed here for a couple years."
Over 10 Triple-A starts, Peralta posted a 6.31 ERA -- albeit in a notoriously pro-hitter environment. Due to the light air and the hitter-friendly nature of Colorado Springs, Counsell has said previously that the team cannot evaluate its players at that level simply by their numbers; thus, on Monday, the Crew's skipper said there were clear indications of progress from Peralta.
"There's been some signs of some good things," Counsell said. "He had a couple starts where the breaking ball was improved and he had a big strikeout start where the breaking ball was really good in a tough pitching environment. I think that's a key for him, is that there's some swing and miss in the off-speed stuff."
• Milwaukee optioned reliever David Goforth to Colorado Springs and recalled reliever Rob Scahill. The Brewers claimed Scahill off waivers from the Pirates on July 12. Across five seasons between Colorado and Pittsburgh, Scahill sports a 3.89 ERA in 104 innings, including a 4.41 ERA in 15 games with the Pirates this season.
"He's a guy that we've seen with Pittsburgh the last couple of years," Counsell said. "He's a sinker baller, so down in the zone is going to be a big deal for him. Our evaluators have always thought highly of him, and so we claimed him."