Janzen joined the PGA Tour in 1989. He has won eight times on the PGA Tour, most notably the 1993 and 1998 U.S. Opens. In 1993, he defeated Payne Stewart at Baltusrol in Springfield, New Jersey, en route to tying the 72-hole U.S. Open scoring record of 8-under-par. Five years later, he beat out Payne Stewart again to win his second U.S. Open, this time at the Olympic Club in San Francisco. He was down five strokes but bounced back marking the best final-round comeback in a U.S. Open for 25 years since Johnny Miller's win in 1973. Janzen also notched a victory at The Players Championship in 1995. The Players is a premiere event on the PGA Tour, unofficially known as the fifth major," and includes the largest purse of the season. He has been featured in the top 20 of the Official World Golf Ranking. Janzen had several opportunities to win additional major golf championships. In 1996, he was in contention at both the U.S. Open and PGA Championship before finishing in the top-10 in both events. He finished fourth at the 1997 PGA Championship after sharing the 36-hole lead at Winged Foot in Mamaroneck, New York. Janzen also played on two American Ryder Cup teams, in 1993 and 1997."