The 1998 Open Championship was a men's major golf championship and the 127th Open Championship, held from 16 to 19 July at the Royal Birkdale Golf Club in Southport, England. In weekend wind and rain, Mark O'Meara won his second major championship of the year and first Open Championship in a playoff over Brian Watts, the 54-hole leader. Three months earlier, O'Meara won the Masters on the final green by sinking a 20 ft birdie putt. At age 41, he became the oldest player to win two majors in a year: Jack Nicklaus (1980), Ben Hogan (1953), and Craig Wood (1941) were all age forty. (Hogan won three majors and turned 41 two weeks after the third.) At the previous Open at Royal Birkdale seven years earlier in 1991, O'Meara was a co-leader after 54 holes, shot 69, and tied for third.

Course

Source: Lengths of the course for previous Opens:

Round summaries

First round

Thursday, 16 July 1998 Source:

Second round

Friday, 17 July 1998 Source: Amateurs: Rose (-2), García (+4), De Vooght (+6), McCarthy (+8), Kuchar (+10).

Third round

Saturday, 18 July 1998 Source:

Final round

Sunday, 19 July 1998 Sources: Amateurs: Rose (+2), García (+12), De Vooght (+19).

Playoff

The four-hole aggregate playoff was played on the concluding holes (15–18). O'Meara birdied the first, while Watts parred, and they halved the next two holes with pars. Watts bogeyed the final hole, while O'Meara parred to win the playoff by two strokes and the Claret Jug.

Scorecard

Cumulative playoff scores, relative to par Source: