Walsh, Lombardi and the NFC West

It's looking like Vince Lombardi or Bill Walsh will claim the top spot in ESPN's ongoing series ranking the greatest head coaches in NFL history.

The third through 20th spots have been assigned, with Don Shula coming in at No. 3.

Winning percentage isn't the best way to evaluate head coaches, of course. If it were, Mike Martz (.624) would come in ahead of Walsh, Tom Landry and quite a few others.

Please accept these grains of salt when reading the chart below. It ranks by winning percentage current NFC West head coaches, with information for Walsh and Lombardi in there as well.

Here's some perspective: Pete Carroll would have to go 34-9 over the next three seasons while winning the Super Bowl each year to approximate Walsh's winning percentage and championship legacy.

Update: I've added to the chart Bruce Arians' record as interim coach for the Indianapolis Colts last season. Being named coach of the year should count for something, right?

Winning Percentages for Bill Walsh, Vince Lombardi and current NFC West coaches