The best designated hitters in baseball history

At 40 years and counting, the designated hitter debate continues in baseball.

Inarguably, though, some of the game's greatest batters have been able to extend or enhance their careers with the DH rule in the American League. Here's one take on the top five designated hitters:

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5. HAROLD BAINES

Baines had a 22-year all-AL career that began in 1980 with Chicago, and by 1987 the DH was his regular position. Over the final nine seasons of his career, Baines appeared in the outfield in only one game. But he kept on because of his bat, turning in one of his best years at age 40 in 1999 when he became an All-Star for the sixth time. Baines hit .322 with 24 home runs and 81 RBIs in just 345 at-bats that season for Baltimore, which traded him to Cleveland that August.

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4. FRANK THOMAS:

Thomas often spoke of the difficulty of being a good DH, given the challenge of staying sharp between at-bats without defense to play in the meantime. But the guy they called the "Big Hurt" was used as a DH more than a first baseman from 1998 through the end of his 19-year career in 2008 and exclusively for his final four seasons due in part to ankle problems. The two-time MVP, another AL lifer who made his mark with Chicago, is a strong candidate for the Hall of Fame when he becomes eligible in 2014, with 521 home runs and a .301 career batting average.

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3. PAUL MOLITOR:

The first DH to win the World Series MVP award, with Toronto in 1993, was a first-ballot Cooperstown inductee with 3,319 hits and 504 stolen bases over his 21-year career. Molitor was an infielder, mostly at third base, when his body allowed it, but persistent injuries steered him toward the DH role by the end of his tenure with Milwaukee. He won his final of four Silver Slugger awards as a DH with Minnesota in 1996.

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2. DAVID ORTIZ:

Ortiz became the leader in career hits by a DH this month, passing Baines with a double at Seattle, the organization he came up with before being traded to Minnesota. Claimed after the 2002 season by Boston, Ortiz has played sparingly at first base over 17 years in the majors but been a fixture among the AL offensive leaders, highlighted by the 54 homers and 137 RBIs he totaled in 2006, both league highs. His career on-base-plus-slugging percentage is a whopping .931.

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1. EDGAR MARTINEZ:

Hamstring problems made Martinez, who began his career as a third baseman, a regular DH. Had he been healthy enough to play in the field more, Martinez might be in the Hall of Fame. He never reached 200 hits in any of his 18 seasons, all with Seattle, but his .418 career on-base percentage was one of the best of his generation. In 2000 at age 37, Martinez hit .324 with 37 home runs and 145 RBIs. He even had four seasons of 46-plus doubles.

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