You think Muirfield isn't fast?!
You can see Francesco Molinari, who is on the green, point at the drive as Schwartzel's ball fed into Molinari and Webb Simpson's group.
As our friend Shane Bacon pointed out, Schwartzel's previous long drive of the year was only 361 yards:
Charl Schwartzel's long drive this season was 361 yards before that one he just hit at 15. #weightroom— Shane Bacon (@shanebacon) July 20, 2013
It's actually tied for the longest drive of the year at PGA Tour events (although Louis Oosthuizen hit a 500-yard drive on the European Tour):
1. Charl Schwartzel -- 450 yards
1. Phil Mickelson -- 450 yards
3. Kyle Stanley -- 428 yards
4. Ian Poulter -- 426 yards
5. Graham DeLaet -- 420 yards