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Jack William Nicklaus (born January 21, 1940), nicknamed The Golden Bear, is an American retired professional golfer. He is widely regarded as the greatest golfer of all time, winning a record 18 career major championships, while producing 19 second-place and 9 third-place finishes, over a span of 25 years. Nicklaus focused on the major championships--Masters Tournament, U.S. Open, Open Championship and PGA Championship--and played a selective schedule of regular PGA Tour events, yet still finished with 73 victories, third on the all-time list behind Sam Snead (82) and Tiger Woods (79).

In 1980, Nicklaus recorded only four top-10 finishes in 14 events, but two of these were record-setting victories in majors (the U.S. Open and the PGA Championship); the other two were a tie for fourth in The Open Championship and a runner-up finish in the Doral-Eastern Open to Raymond Floyd via his chip-in birdie on the second hole of a sudden-death playoff. These victories and placements more than justified the work Nicklaus put in toward his game during the off-season. Nicklaus set a new scoring record for the 1980 U.S. Open with an aggregate of 272, eclipsing his earlier record of 275 from 1967 over the same golf course. That record, while since having been tied by three other players, stood until Rory McIlroy's 268 in winning the 2011 US Open. This was Nicklaus's second major win at Baltusrol Golf Club. Nicklaus opened with a record-tying 63 in round one and fought off his playing partner of all four rounds, 1978 Colgate World Match Play Championship winner, Isao Aoki. Entering the final round, Aoki had caught Nicklaus after three consecutive rounds of 68, but over the course of the last day, Nicklaus pulled away by two shots. Each player birdied the final two holes for a dramatic finish. Aoki's aggregate of 274 was the lowest score for a U.S. Open runner-up. Nicklaus' win was his fourth and final victory in the championship, tying him with Willie Anderson, Bobby Jones, and Ben Hogan. Nicklaus referred to this win as "by far the most emotional and warmest reaction to any of my wins in my own country". In the 1980 PGA Championship, Nicklaus set another record in winning the championship by seven shots over Andy Bean at the Oak Hill Country Club, largely due to exceptional putting. Nicklaus shot an even-par 70 in the first round followed by three successive rounds in the 60s over the difficult course, and was the only player to break par for the 72 holes. For the week, the field averaged 74.60 strokes while Nicklaus averaged 68.50. This was Nicklaus' fifth and final victory in the PGA Championship, which elevated him to record-holder for the most wins in the stroke-play era, and which tied him with Walter Hagen for the most wins overall, since Hagen's victories were all during the match-play era. Nicklaus' seven-shot winning margin remained the largest for the stroke-play version of the championship until Rory's McIroy's 2012 victory. This victory also made Nicklaus the only player since Gene Sarazen in 1922 and Ben Hogan in 1948 to win the U.S. Open and PGA Championship the same year (subsequently equaled by Tiger Woods in 2000). Between 1981 and 1985, Nicklaus accumulated seven more top-10 placements in major championships, including three runner-up performances. He won only twice on the PGA Tour during this period, the Colonial National Invitation in 1982 and his own Memorial Tournament in 1984 for the second time, defeating Andy Bean in a sudden-death playoff to become the tournament's first repeat champion. In 1983, Nicklaus closed out the PGA Championship and World Series of Golf with brilliant final rounds in the mid-60's, and passed many players to move into contention, but finished runner-up in each to Player of the Year Hal Sutton and Nick Price, respectively, who dominated the tournaments from start to finish. Despite not winning a PGA Tour event in 1983, Nicklaus finished 10th on the PGA Tour money list, and passed a significant milestone by becoming the first player to eclipse the $4 million level in career earnings. In 1985, Nicklaus finished second to Curtis Strange in the Canadian Open, which marked his seventh and final second-place finish in that tournament; this is a record for that event. These seven runner-up finishes came over the course of 21 events--or one second-place finish for every three tournaments played--and does not include a third-place finish in 1983, one shot out of the playoff between John Cook and Johnny Miller. During the five-year period between 1981 and 1985, the Ryder Cup matches provided Nicklaus with two bright spots. He completed his competition as a player in style by contributing a perfect 4-0-0 record (inclusive of a 5 & 3 anchor singles match win over Eamonn Darcy) in 1981, and captained the United States team in 1983 to a one-point win over Europe. Nicklaus became eligible to join the Senior PGA Tour, now known as PGA Tour Champions, when he turned 50 in January 1990, at which point he declared, "I'm never satisfied. Trouble is, I want to play like me--and I can't play like me anymore." He then quickly won in his first start on the Tour, The Tradition, also a Senior Tour major championship. Nicklaus would go on to win another three Traditions--the final two in succession--while the most anyone else has won is two. Later in the year, Nicklaus won the Senior Players Championship by six shots over Lee Trevino for his second win of the year, and also his second major of the year by shooting a record 27-under par 261. The next year, in 1991, Nicklaus won three of the five events he started in, those being the U.S. Senior Open at Oakland Hills by firing a 65 in a playoff against Chi-Chi Rodriguez and his fine round of 69, the PGA Seniors Championship and The Tradition for the second year straight. These, again, were all majors on the senior circuit. Nicklaus has won all the senior majors with the exception of the Senior Open Championship (also known as the Senior British Open). However, he never played in that event until after he turned 60, and it was only elevated to a major in 2003. After a winless year in 1992, Nicklaus came back to win the U.S. Senior Open for the second time in 1993 by one shot over Tom Weiskopf. Also in that year he teamed up with Chi-Chi Rodriguez and Raymond Floyd to win the Wendy's 3-Tour Challenge for the Senior PGA Tour team. In 1994, Nicklaus won the Senior PGA Tour's version of the Mercedes Championship for his only win of the year. The Tradition was his again in 1995, in a year where he made the top 10 in all of the seven tournaments he entered in. His 100th career win came the next year, when he won the Tradition for the fourth time, and second time in succession. He made a double eagle in the final round. Nicklaus closed the final 36 holes with back-to-back seven-under par rounds of 65 to shoot a 16-under par 272 and win by three shots over Hale Irwin. This was to be his last win on the Senior PGA Tour, and the last official win of his career. CANNOTANSWER

Jack Nicklaus