Vernon Wells slotted in as the Yankees' DH against right-hander Alexi Ogando on Tuesday, replacing Hafner, who entered the game hitless in his last 13 at-bats and has just two hits in his last 25 at-bats. Hafner grounded out sharply as a pinch-hitter in the ninth inning of Tuesday's 5-4 win.
The slump is not a new development for Hafner, who has struggled mightily since a solid April debut in pinstripes. Hafner entered Tuesday with a .172 average, six homers, 20 RBIs, a .256 on-base percentage and a .296 slugging percentage since May 1.
"I don't really see a lot that's different in his setup or his swing," Yankees manager Joe Girardi said. "He's not being productive is what I see. It's frustrating for him, it's frustrating for us, because we believe that he can hit and we believe he's much better than what he's shown these past few months."
Hafner was signed to a one-year, $2 million contract by the Yankees in February, essentially as a replacement for Raul Ibanez, as general manager Brian Cashman referred to both players as "big, hairy monsters."
But Hafner has been unable to approach the impact that Ibanez had for the Yankees last season, as well as the 24 homers that Ibanez has slugged for the Mariners this year. Hafner is batting .209 with 12 homers and 37 RBIs in 79 games.
"It's been really frustrating," Hafner said. "This is a great situation for me here, and [Yankee Stadium] is a good ballpark for me to hit in. I feel like I can go out there and play at a high level and play like I did the first month. There's no reason why I can't do that. It's been extremely frustrating."
Hafner said that his right shoulder, on which he underwent an MRI exam and cortisone injection in May, has not been an issue. His problems have been more related to timing and feel at the plate.
Asked how much longer the Yankees could stick with Hafner, Girardi replied, "I guess you could go the rest of the season, right?"
"This game's tough. Hitting is tough. It's kept us all up at some point in our careers at night because it's difficult. I'm not giving up on him. He's not in the lineup today, but that doesn't mean that I'm giving up on him. We know that we need him to produce, and somehow, we have to find a way to get it done."