MESA, Ariz. -- The A's shut down Brady Basso with a shoulder strain Tuesday, interrupting what had been a solid spring training for the left-hander as he tried to earn a job with the big league club after making his Oakland debut last season.

The 27-year-old Basso, who went 1-1 with a 4.03 ERA in seven appearances for the A's, had not allowed a run over 4 1/2 innings, The team said before departing for its spring training game against Texas there was no timeline for his return.

In other injury news, left-hander Ken Waldichuk began throwing in the bullpen as he continues to work his way back from Tommy John surgery last year. Waldichuk underwent the procedure in May and the recovery was estimated at 13 months.