Oregon star second baseman Drew Cowley will miss four weeks due to a broken hamate bone, head coach Mark Wasikowski announced Thursday.

“He broke his hamate bone on the first swing at Stanford on Friday night,” Wasikowski said. “He played with it broken for the rest of the game, and then he had his hamate bone removed after that surgery. So he’s out four weeks. He’ll be back at the start of April.”

Cowley was 21-for-41 at the plate going into March 11’s series opener against Stanford, when he went 0-for-4 with four strikeouts. He had only struck out four times the entire season before that, so the injury was clearly bothering him during the game.

Cowley had one of the top batting averages in all of college baseball before missing the next six games. His name has since been removed from leaderboards due to lack of plate appearances.

“It’s a big loss,” Wasikowski said. “We’ve got other players that are good players, but losing a guy that’s possibly one of the best hitters on the west coast in the country is never fun.”

While the news is unfortunate for the Ducks, an April return means the four-week period has already begun. Meanwhile, Gavin Grant has done a tremendous job in Cowley’s place, hitting .339/.426/.627 out of the nine-hole. Oregon is tied for the 16th-most runs in Division 1 baseball this season.

The Ducks are also without their ace on the mound, Adam Maier. The sophomore transfer left his March 4 start against UC Santa Barbara with an undisclosed forearm injury. Wasikowski hasn’t provided any updates on him.

Pitching coach Jake Angier said last week that Maier was in the “figuring out stage” and that he had some meetings to take care of. Joe Dyle of Prospects Live reported on March 12 that Tommy John surgery is not yet on the table and that the team was getting a second opinion.

Andrew Mosiello also hasn’t pitched since March 5. Wasikowski said Thursday that he’s dealing with back spasms.

Oregon (14-6) begins a three-game series against USC Friday at 4 p.m.