I'm not going to go into the stats. They speak for themselves. When Kuper is off the field, we Manning takes more sacks and more hits. When he's on the field our rushing average is better and Manning is better protected. I haven't heard what happened with his ankle, but I assume it is post game swelling that hadn't gone down enough and they wanted to rest him for Baltimore. Hopefully it wasn't re-injured.
Regardless, without Kuper our team is worse. With him, our team is better. We need our best offensive lineman on the field.