In 15 2/3 innings over 18 appearances this season, Salas is 0-3 with a 6.32 ERA. The right-hander has allowed 23 hits and walked 11 batters (two intentionally).
That's a far cry from his work in 2011, when he went 5-6 with a 2.28 ERA in 75 innings over 68 appearances and saved 24 of his 30 opportunities.
"Last season, he was controlling the corners of the strike zone early and controlling the counts and working ahead, and that made his changeup that much better," manager Mike Matheny said. "We're seeing him work from behind and catching a lot of plate right now. So it's just a little different right now. We have to get him fixed."
Salas had an 0-1 record and 4.50 ERA in eight innings over 11 appearances in April, in which he allowed four earned runs on 12 hits, struck out 11 and walked two. In May, he's 0-2 with an 8.22 ERA, and has allowed seven earned runs on 11 hits over 7 2/3 innings, with 10 strikeouts and seven walks.
"The problem is we've seen some really good outings that make us think [he's OK], and then you've seen a couple others that just haven't been quite him," Matheny said. "It's hard to figure out what that right spot is. Some guys thrive when you put them in a tougher spot, and then other guys it doesn't matter the spot if they are not right. We're just kind of sifting through that."