The Oakland A's reinstated infielder Hiro Nakajima from the 15-day disabled list and optioned him to Triple-A Sacramento, the club announced Thursday.

Nakajima, who left Japan to sign a two-year, $6.5 million contract with the A's in the winter, began the season the season on the disabled list with a strained left hamstring. He began a rehab assignment with Sacramento May 3 and hit .265 with four doubles and five RBIs in 13 games.

Nakajima batted .229 over his first nine games but has hit safely in each of his last four contests (5 for 14, .357). He appeared in 11 games at shortstop but also made one appearance each at second base and third base.