X-rays negative, MRI coming for Kolb

After the Arizona Cardinals got a glimmer of John Skelton post-ankle injury (two for 10 with a pick), they likely have renewed appreciation for Kevin Kolb. But Kolb has a rib injury, the severity of which is unknown. Coach Ken Whisenhunt said Monday that X-rays of Kolb’s sternum and ribs were negative.  An MRI is…