PEBBLE BEACH, CALIFORNIA - JUNE 12: Brooks Koepka of the United States warms up on the driving range during a practice round prior to the 2019 U.S. Open at Pebble Beach Golf Links on June 12, 2019 in Pebble Beach, California. (Photo by Christian Petersen/Getty Images)

How long do pro golfers usually warm-up for?

Brooks Koepka arrived 45 minutes before his tee time on Sunday at the WGC-FedEx St. Jude Classic. Is that normal? And how long do players usually warm up for?

Golf