Arenado making case for lineup spot

SCOTTSDALE, Ariz. -- The Rockies entered Sunday's tilt with the A's averaging seven runs a game, the kind of offense they're counting on as a young pitching rotation continues to mature after starters posted a 5.81 ERA last season and won only 29 games.

So when top prospect Nolan Arenado belted his third Cactus League dinger Sunday in the second inning -- a towering solo shot to left -- and drove in both runs from a lineup filled to the brim with seven likely Opening Day starters, the buzz only grew about the 21-year-old's potential and the contributions he could make with Colorado.

Arenado has played a season each in Casper (Rookie), Modesto (Class A), Ashville (High A) and Tulsa (Double-A), and he is slated to play at Triple-A Colorado Springs this year after Chris Nelson solidified his hold on third base with a .301 campaign in 2012, knocking nine homers and 53 RBIs in 111 games for the Rockies.

"You don't want to ever put a limit on a kid like that and say he can't win a job," manager Walt Weiss said Sunday. "He's made a good impression. Chris Nelson had a very good second half last year, too."

Nelson hit .345 from Aug. 1 on, best among all Major League third basemen, including Triple Crown-winner Miguel Cabrera's .344.

"We got another month to go, and the picture will get a little clearer with some more games under our belt," Weiss said. "But Nolan's certainly made a very good impression."