Although the injury will not require surgery, it will delay Eaton's highly- anticipated rookie campaign.

Eaton said he started to feel discomfort in his elbow roughly two weeks ago. Over 20 spring training games this season, Eaton was batting .390 with 23 hits and 10 RBI before the injury.

In 22 appearances with Arizona last season, Eaton batted .259 with two homer and five RBI.