The Rockies, dissatisfied with the lack of athleticism, plan to shake up their bench, major-league sources say.

The players most in jeopardy: Infielders Alfredo Amezaga and Jose Lopez.

The Triple A players who could inject the most energy and speed: Infielders Eric Young Jr. and Chris Nelson.

It is not known whether the Rockies intend to make one move or two. But the team became less athletic after it demoted third baseman Ian Stewart to Triple A.

Lopez, signed to a one-year, $3.6 million contract, has a minor-league option remaining, but his five-plus years of major-league service gives him the right to reject any demotion and become a free agent. If he chose that route, he likely would clear waivers and sign a Triple A contract with another club.

Lopez, who has a .525 OPS in 128 plate appearances, is generating minimal trade interest, sources say. The Rockies would be responsible for the balance of his salary regardless of whether he stayed in the organization.

Amezaga, who did not play in the majors last season after undergoing microfracture knee surgery, signed with the Rockies as a minor-league free agent. He, too, would be exposed to waivers if the team tried to send him to the minors.

Young currently is batting .363 for Colorado Springs with a 1.006 OPS and 17 stolen bases in 18 attempts. Nelson is batting .312 with an .853 OPS.

-Ken Rosenthal