BOSTON (CBS) – Grady Sizemore has been raising some eyebrows to  start spring training, and his impressive start has put Jackie Bradley Jr.’s center field spot in jeopardy. Andy Gresh believes that it’s time for the 23-year-old prospect to step it up and show what he’s made of.

Citing an article written by Christopher Evans in the Boston Herald, Grady Sizemore is providing some very real competition for the starting job. The injury-plagued Sizemore is finally healthy, and has been clocked at 4.2 seconds running from home to first. By comparison, the light-footed outfielder ran it at 4.14 seconds in what Scott Zolak dubbed his “MVP-caliber” days.

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Gresh was quick to note that Sox fans should still temper their expectations for him, and he described Sizemore as the perfect back-up outfielder. Gresh cited Sizemore’s ability to play all three positions and his durability issues as reasons why he fits the mold as a Red Sox backup.

Then Gresh laid down the gauntlet for Bradley Jr.

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“This is a challenge he should be able to overcome, and if he can’t, my mind’s going to wonder — is he really a part of the long-term future of this organization?” Gresh said. “What are you gonna do, kid? Are you going to be a once-thought-of-as a great prospect that we’re going to move on from? Or are you going to step up and actually do something? It’s time for him to do the latter.”

You can listen to the entire segment below here:

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