Hamels wasn't ready for the start of the season after feeling discomfort in his pitching arm in November. The left-hander was diagnosed with biceps tendinitis.
"We'll fit him in there in L.A.," manager Ryne Sandberg told reporters before Friday's game against Colorado. "We're still discussing it, but as we speak we're leaning toward Wednesday."
Hamels started Thursday for Class-A Clearwater, allowing one run over seven innings. He walked one, struck out three and threw 81 pitches.