MESA, Ariz. - The A's are excited about 2016 top pick A.J. Puk, that much was apparent by the crowd the lefty attracted for his first "live" bullpen session Tuesday.
Among those watching closely were executive vice president of baseball operations Billy Beane, general manager David Forst, manager Bob Melvin and pitching coach Curt Young.
Puk, who shaved about 20 pounds off his 6-foot-7 frame over the winter, looked strong against a group of hitters that included touted infield prospects Franklin Barreto and Yairo Munoz.
Melvin in particular liked the way Puk, the No. 6 overall pick out of the University of Florida, worked his curve ball into the mix. That's a pitch he hadn't used since high school, but he dusted it off back in the fall instructional league with some encouragement from minor league pitching coordinator Gil Patterson, and he's working to sharpen it this spring as a complement to his fastball, slider and changeup.
"It's just nice to have another pitch that's slower than my other three pitches," Puk said before Tuesday's workout.
"It's a four-pitch mix," Melvin said. "He's really starting to distinguish between this slider and curve ball. It was quite a crowd around his cage too. When you're a young kid you tend to notice that, but I thought he responded really well."
Puk, 21, is rooming with shortstop Richie Martin, a teammate at Florida whom the A's made their top pick in 2015. They also lived near each other in Tampa this offseason and worked out together.
Puk comes off very quiet upon meeting him, but Martin warns against being fooled.
"It takes him a while, but once he feels comfortable he'll break out. You'll see."
Melvin was impressed with Puk's physical shape, saying he's fielded his position well in pitchers' fielding drills.
CAMP BATTLE Jesse Hahn will start the A's Cactus League opener Saturday against the defending World Series champion Chicago Cubs. It'll be a chance for Hahn to make an early impression in his bid for the fifth starter spot.
"After the year he had (in 2016), it's important for him this year. We have to show some faith in him," Melvin said. "He performed well for us the year before. Last year wasn't really consistent. We'll try to get him out there and get him off to a good start."
Kendall Graveman will take the ball in Sunday's spring home opener against the Angels. Sonny Gray and Sean Manaea both will pitch Monday against the Giants and Jharel Cotton and Andrew Triggs will be among the group throwing Tuesday against the Indians.
PROSPECT WATCH: Sean Murphy, the A's third-round pick in June, has shown a very strong throwing arm early in camp. Is it any wonder Melvin, an ex-catcher, was impressed?
"The kid can throw, it's special," Melvin said. "We really like him."
NOTEWORTHY: Still no word on when reliever Santiago Casilla will arrive at camp from the Dominican Republic. Melvin said he isn't concerned at this stage, and noted that Casilla has been working out at the team's complex in the Dominican Republic and gave a motivational talk to the younger players there.