In March 2017, left tackles Matt Kalil and Riley Reiff were free agents. It was reported that Kalil, drafted No. 4 overall by the Vikings in 2012, picked Carolina over the Vikings in part because he wanted to play alongside his brother, Ryan.

Reiff signed with the Vikings as his replacement.

Reiff was good last year — not great, but an upgrade over Kalil in terms of both durability and performance. Kalil wasn't awful with Carolina, but he allowed more pressures and had a lower pass-blocking grade than Reiff, per Pro Football Focus.

And now we come to this season, where the Vikings are facing a ton of questions and injuries on the offensive line. One of the mainstays in camp, again, has been Reiff.

Kalil, on the other hand, is experiencing knee problems. Imagine if he was in Minnesota right now, with Nick Easton already out and other nagging injuries plaguing the line. It would be a full-blown panic.

Read Michael Rand's blog at startribune.com/randball. michael.rand@startribune.com.