ST. PETERSBURG -- Prior to Sunday's game with the A's, the Rays optioned right-hander Ryne Stanek to Triple-A Durham and activated right-hander Jumbo Diaz from the disabled list.
Stanek is 0-0 with a 5.59 ERA in 11 games for the Rays this season.
Rays manager Kevin Cash cited controlling the count as a facet of pitching Stanek needs to work on while at Durham.
"I think count-control is a big separator for a lot of guys," Cash said. "That was the big message that we gave [Stanek]. There's a big difference between working ahead and behind at this level. And at times, it's big at Triple-A, but it seems one through nine, it's pretty big here. The more he can command getting strikes early, it will help his stuff play out.

"He's going to be fine, though. We're confident of that. And I think part of this is because of an innings crunch; what took place yesterday. But at the same time, it would probably do him good to go down there and freshen up and get to feeling good about himself."
Stanek, the Rays' No. 16 overall prospect according to MLBPipeline.com, noted he's learned "it's kind of a different game up here."
"If you fall behind, they make you pay for it a lot more," Stanek said. "As you go, you get more comfortable throwing offspeed pitches behind in the counts, and then just staying in control in those counts to be most effective."
Stanek said he feels as though he learned a lot.
"And I definitely feel like I can do this," Stanek said. "I'm just going to take this, go down, work on some things, and hopefully be back soon."
Diaz returns to the Rays' bullpen after going on the DL on May 25 with right-arm fatigue. He is 0-3 with a 5.49 ERA in 21 games for the Rays.
"I feel good any time they need me," Diaz said. "I'm happy to be back and [to] help the bullpen."