Matt Olson undergoes surgery on hand

Athletics first baseman Matt Olson underwent successful surgery on his right hand on Friday, the club announced. An A's spokesman declined to reveal a timetable for Olson's recovery, but the slugger could be sidelined for an extended period of time.

The procedure, which involved a right hamate excision, was performed by Dr. Steven Shin in Los Angeles.

Olson sustained the injury on Thursday at the Tokyo Dome in Japan, leaving Oakland’s 5-4 loss to Seattle in the sixth inning with pain in his right hand. He told reporters afterward that he “felt pain pretty much on contact,” when he fouled off a slider from the Mariners’ Yusei Kikuchi in the fifth inning. Olson managed to single later in the at-bat and ran the bases, but the pain grew worse as time went on, and he was removed before the top of the sixth.

The course of Olson’s recovery is unclear, pending an official announcement. Typically, after a period of immobilization, a person can resume regular activity in six to eight weeks. But hamate injuries can be highly problematic for hitters, sometimes even after they are cleared to return.

Players such as the Astros’ Yuli Gurriel and the Rangers’ Delino DeShields had hamate surgery last spring and missed only three to four weeks. In 2011, Giants third baseman Pablo Sandoval missed 40 games following hamate bone removal in his right hand and still led the team in batting average, hits, home runs, extra-base hits, RBIs and runs.

Other times, things don’t go so smoothly. For example, Giancarlo Stanton sustained a broken hamate bone while playing for the Marlins in late June 2015, and after initially being expected to miss four to six weeks, wound up unable to return to action at all that season.

Olson’s injury is another big blow for the A’s, whose 2019 season is off to an inauspicious start. Coming off 97 wins and a postseason appearance in ‘18, Oakland not only dropped two straight games in Japan but also learned that top prospect Jesus Luzardo -- a left-hander who figured to be a major part of the team’s rotation -- would have to be shut down for four to six weeks with a muscle strain in his left shoulder.

Olson, who turns 25 next Friday, had proven himself durable in 2018, when he played in all 162 games. Following a fantastic 59 games for the A’s in ‘17 (.259/.352/.651 with 24 homers), the left-handed batter did see his production slip a bit. Even so, he smacked another 29 homers and drove in 84 runs while slashing .247/.335/.453 and earning an American League Gold Glove Award for his defensive work at first base.

While Olson started 152 games at first last year, Mark Canha also started nine and Chad Pinder one. In all, the right-handed hitting Canha has played in 98 career games at the position.