Jeremy Guthrie (shoulder) will face hitters at Petco Park Tuesday before beginning a rehab assignment with Triple-A Colorado Springs. He might need just one rehab outing before rejoining the Rockies rotation if he feels well. Guthrie has been nursing some stiffness in his AC joint, which was the result of a bike accident. He posted a 5.92 ERA and 1.44 WHIP over four starts before the injury.