SAN DIEGO -- Anthony Rizzo tore up the Pacific Coast League to the point that the San Diego Padres figured they had no choice but to call him up.
The slugging first baseman will join the Padres on Thursday after spending just two months at Triple-A Tucson. He is one of two prized prospects acquired by the Padres when they traded three-time All-Star first baseman Adrian Gonzalez to the Boston Red Sox in December in a five-player deal.
Rizzo batted .365 with a .715 slugging percentage, .444 on-base percentage, 16 homers and 63 RBIs at Tucson.
"We wanted him to get some seasoning," general manager Jed Hoyer said after the Padres lost 5-3 to the Colorado Rockies on Wednesday. "This is frankly ahead of the schedule we had imagined when we acquired him. We thought he was a guy that if he pushed it he could be a September callup and could help us in 2012. He's played so well in spring training and this year that he really forced us and pushed the clock. Going into the season this wasn't the timing we expected. I'm proud of him to force us to make the move earlier."
Hoyer said there's a "buzz" about Rizzo joining the Padres.
"I hope it's not only because he was part of the Adrian Gonzalez deal. I hope it's because he's played exceptionally well at Triple-A and that people are excited to see him play and I hope the same thing will happen when we call up future players if they have this kind of performance," Hoyer said.
Rizzo flew to San Diego on Wednesday to have his left thumb examined by a specialist in the last step before joining the big league squad.
Rizzo was hurt May 31 when he collided with an umpire. He sat out the following two games, played three games and then sat out Monday and Tuesday. He had an MRI on Tuesday. The Padres wanted to have him checked by a specialist before bringing him up.
Hoyer said he originally thought about bringing up Rizzo for a stretch of interleague games starting June 17 at Minnesota, followed by a series at Boston from June 20-22. The thought was to have Rizzo play first base and Brad Hawpe, who's already moved from first base to right field, be the designated hitter.
But manager Bud Black talked Hoyer into making the move earlier.
"As we started talking about it, Buddy said, 'Well Jed, why not right now?' That was probably four or five days ago. He really convinced me," Hoyer said.
Fans have been clamoring for the last-place Padres to call up the 21-year-old Rizzo, who had never played above Double-A until he started this season with Tucson.
In 2008, Rizzo was limited to 21 games after being diagnosed with limited stage classical Hodgkin's Lymphoma.
Hoyer said it's easier to bring up Rizzo now since the Padres aren't struggling as badly as they were earlier in the season.
"I didn't think it was fair to him, 100-plus plate appearances into his career with the Padres, to bring him up to fix a team that was struggling," Hoyer said. "Now we're playing better, today notwithstanding, and I don't think he's a savior of a team now. I think he's coming up and he can be a part of something."
The other top prospect obtained by the Padres in the Gonzalez deal is right-hander Casey Kelly, who's with Double-A San Antonio.
The Padres have struggled all season, particularly at home.
Rizzo is expected to start against the Washington Nationals on Thursday night. Black said he'll hit somewhere between fifth and seventh.
After trading Gonzalez, the Padres signed Hawpe to play first base even though he had only played a handful of games there during his big league career. He was a first baseman in the minors but moved to the outfield when he made his big league debut with Colorado because Todd Helton was playing first for the Rockies.
Hawpe made his third straight start in right field on Wednesday.