Martinez will start Monday's game against the Brewers, Kevin Acee of The San Diego Union-Tribune reports.
Martinez struck out six in four scoreless innings as a long reliever Wednesday against the Phillies after starting in his first six appearances this season. However, he'll reclaim a starting role in Monday's series opener after Mike Clevinger (triceps) was placed on the 15-day injured list. If the Padres choose to remain with a six-man rotation in Clevinger's absence, Martinez will likely continue to work as a starter over his next few appearances.