MESA, Ariz. -- Plenty of hype followed A.J. Puk into Thursday's tilt under the lights, but the lefty's time on the mound was short-lived.
Oakland's top prospect, who had not allowed a run in his previous eight innings this spring, was touched for four in just 2 2/3 innings against the Mariners.
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Puk faced one over the minimum through the first two innings before his command betrayed him in the third. Two singles, two walks and nearly 40 pitches later, Puk was lifted with two outs in the frame, and reliever Eric Jokisch proceeded to walk his first batter and surrender a grand slam to Taylor Motter, inflating Puk's final line.
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"I was a little erratic with my pitches," said Puk, who threw 63 pitches. "I wasn't as aggressive with my fastball as I'd like to be. I threw a lot of offspeed. I just wasn't able to get it done."
Puk stuck with his two-seam fastball, shying away from using his four-seamer, which can reach the upper 90s.
"We know he has the ability to throw that pitch and strike people out," manager Bob Melvin said. "I think what I've been most impressed with this spring is he's been able to do it in other ways; just got away from him in the third inning."

Puk said he felt fine physically throughout.
"I felt fine, everything feels good," he said. "Just one of those innings where my pitch count kind of came up on me and I had to leave.
"You're going to have days like that, you just got to work to fight through it."
Said Melvin: "I would have loved to have seen him try to get out of it, but maybe just a little off today with his command and they made him work a lot in that last inning."
Speculation surrounding Puk's potential to break camp with the club, despite having zero experience above Double-A, could cool now.
Camp battles
Paul Blackburn fared better, striking out six over four scoreless innings against his former organization. Blackburn, who yielded two hits and walked one, is sitting on a spring ERA of 3.86. It's looking extremely likely that he'll land one of three open rotation spots.

"It's not easy to come in and pitch three or four innings like that in the middle of the game, and he's been able to do it a couple of times," Melvin said. "Kept the ball down, keeps it on the ground, that's what he does."
Lucroy nearing debut
New A's catcher Jonathan Lucroy is set to make his green-and-gold debut Saturday in split-squad action against the Mariners at home. He'll be paired with lefty starter Sean Manaea.
Up next
Right-hander Daniel Mengden and the A's will host the Indians at Hohokam Stadium on Friday, with first pitch scheduled for 1:05 p.m. PT. Relievers Blake Treinen, Emilio Pagan and Liam Hendriks are also expected to appear in the game. Listen to an exclusive audio webcast.