BALTIMORE -- The A's reinstated third baseman Danny Valencia from the disabled list before Friday's rained-out series opener in Baltimore and optioned Tyler Ladendorf to Triple-A Nashville.Valencia missed the minimum 15 days while nursing a strained left hamstring, playing in two rehab games with Class A Advanced Stockton this week.

BALTIMORE -- The A's reinstated third baseman Danny Valencia from the disabled list before Friday's rained-out series opener in Baltimore and optioned Tyler Ladendorf to Triple-A Nashville.

Valencia missed the minimum 15 days while nursing a strained left hamstring, playing in two rehab games with Class A Advanced Stockton this week. He had one hit, a home run, in seven at-bats and said Friday, "I felt good enough to be activated today."

"I don't think it's one of those things that heals 100 percent, but I don't think anyone is 100 percent right now anyway," Valencia said. "I'm excited to be back with the boys."

"Since he's been here, he's been a force for us," A's manager Bob Melvin said. "Regardless, we have depth to work around it when anybody is either hurting or on the DL, but it's nice to have that kind of power, especially in a ballpark like [Camden Yards] where home runs tend to pop up from time to time here, so it's good to have him back."

Valencia was hitting .294 in 14 games before suffering the injury, at which point the A's turned to utility man Chris Coghlan to fill in at third base. Coghlan has just three hits in his last 10 games, and his .155 season average is the second-lowest mark among qualified batters in the American League.

Worth noting

• Right-hander Henderson Alvarez made his fourth Minor League rehab start on Thursday and his second with Triple-A Nashville, allowing one run on three hits with three walks and three strikeouts in 4 2/3 innings. He totaled 77 pitches, 46 for strikes.

Melvin said Alvarez, who underwent shoulder surgery last July, may only need to make two more rehab starts before joining the A's rotation.