"He's been throwing 95 [mph] with a wipeout breaking ball," Melvin said. "When he's gotten in trouble a little bit is when he's tried to throw some changeups and establish that third pitch."
That third pitch likely won't be necessary in any big league role Abad would fill.
"But it's always good to work on things," Melvin said.
Abad is out of options, but Drew Pomeranz and Joe Savery still are in contention as second bullpen lefties. Pomeranz, acquired in the offseason trade that sent Brett Anderson to the Rockies, has been a starter nearly all of his short career, but he appears headed toward a relief role in the A's organization.
"We're going to shorten him up and look at him in shorter stints," Melvin said, "look at him against left-handers."
Chris Gabel is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.