OAKLAND, Calif. — Boston right-hander Daisuke Matsuzaka has been placed on the 15-day disabled list after his second straight poor start to open the season.

Matsuzaka didn't make it to the second inning Tuesday night against the Oakland Athletics, giving up five runs and five hits on 43 pitches.

The Japanese star won three games while winning the MVP award at the World Baseball Classic this spring, but Boston manager Terry Francona thinks the extra work has caused trouble early in the regular season. Matsuzaka was 18-3 last year, but is 0-1 with a 12.79 ERA this season.

After Tuesday's game, the Red Sox said Matsuzaka has "arm fatigue." Speaking through an interpreter, Matsuzaka claimed he felt fine.