An agreement reached yesterday between the Philadelphia Phillies and Houston Astros for reliever Wilton Lopez has yet to become official, CBSSports.com insider Danny Knobler confirmed Thursday.

CBSSports.com's Jon Heyman reported Wednesday the two clubs had agreed to a deal sending Lopez to Philadelphia in exchange for "minor league players." Lopez, 29, posted a 2.17 ERA and 2.70 FIP in 66.1 innings in 2012.

Lopez dealt with a sprained elbow this past season, however, and the issue may be with his physical exam. Brian McTaggart of MLB.com says Lopez was in Philadelphia for an examination Wednesday.

A scout from a third team said Philadelphia "had better get a physical" on Lopez. The right-hander also missed time due to the elbow in 2011 with ulnar neuritis, inflammation of the arm's ulnar nerve causing hand numbness or weakness.

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