SCOTTSDALE, Ariz. -- Trevor Bauer made it look easy.

Making his debut against big leaguers, the No. 3 pick in last June's draft retired all six batters he faced Saturday and an Arizona Diamondbacks split-squad and the Colorado Rockies tied 1-1 in 10 innings.

The 21-year-old right-hander from UCLA struck out two and induced four groundballs in his outing.

"At the core level, you throw strikes. They're hitters. They still have to hit it," Bauer said. "It was more of a competition against myself, as it always is, to try to see if I can execute pitches."

Colorado left-hander Drew Pomeranz -- a top pick in 2010 -- struck out two, walked one and allowed a hit in two scoreless innings.

Catcher Ramon Hernandez had two of the Rockies' four hits, including an RBI single that tied the game 1-all in the fourth.

A sellout crowd of 12,528, a single-game record for Salt River Fields

at Talking Stick, attended the teams' first spring game of 2012.

Bauer struck out Dexter Fowler and Tyler Colvin, and he got Carlos Gonzalez, Troy Tulowitzki and Michael Cuddyer to ground out. He threw seven of his 22 pitches in the first innning.

"Today was a pretty efficient outing, especially for the first one of the spring," Bauer said. "I was pleased with my control and command and pretty happy with all of it."

As part of his warmup routine Bauer played long toss in the outfield, throwing up t0 360 feet on the warning track.

Last year, Bauer went 38-4 with a 2.36 ERA for UCLA, winning the Golden Spikes Award for the top college player. He went on to pitch in high Class-A and Double-A for the Diamondbacks.

Bauer started Saturday in place of prospect Tyler Skaggs, who was scratched because of tenderness in his left shoulder. Diamondbacks manager Kirk Gibson said Skaggs is doing fine and will throw a bullpen Sunday.

Gibson liked Bauer's debut against major leaguers.

"Some of his secondary pitches were better than I've seen any time he's thrown so far," Gibson said.

Pomeranz, the fifth overall pick of the 2010 draft out of Mississippi, was pleased with his outing. The 23-year-old is expected to be part of Colorado's starting rotation after he made four starts with the team last September in his first major league action. He joined the Rockies last August as part of their trade with the Cleveland Indians for Ubaldo Jimenez.

"Everything felt good today -- fastball, curveball, changeup," Pomeranz said. "That's the best my rhythm has been. I've been kind of working on keeping my hands up during my delivery."

Gerardo Parra went 1 for 3 with an RBI for Arizona.

Arizona took a 1-0 lead in the fourth after Paul Goldschmidt walked, advanced to third on Geoff Blum's double and scored on Parra's groundout. The Rockies tied the game in the bottom of the inning on Hernandez's single.

Game notes
An Arizona split-squad faced the San Francisco Giants in Scottsdale. ... The Diamondbacks announced both of their weekend games are sold out. They also play the Giants on Sunday. Arizona drew a franchise-record 189,767 fans to Salt River Fields in its first season at the ballpark. .The fire alarm went off in the seventh inning, but it was a false alarm and fans were not asked to evacuate the complex.