Nelson isn't guaranteed to keep his spot in the rotation going forward, Tom Haudricourt of the Milwaukee Journal Sentinel reports.
Nelson has made three starts for the Brewers this season after a long absence due to shoulder surgery. He's allowed 13 runs in 12 innings while walking 10 batters. The team would likely love to give him the chance to work through his struggles but can't afford many more poor starts while in the middle of a competitive playoff race.