OCT. 17, 2004: David Ortiz will always be remembered for his big hits in the clutch, and none was much bigger than this game-winning home run against the New York Yankees in the 12th inning of Game 4 of the 2004 American League Championship Series. The win started Boston's climb from a 3-0 series deficit all the way to its first world championship since 1918. As the Red Sox start the 2016 playoffs, Ortiz is shooting for his fourth World Series title.

SEPT. 6, 2004: Ortiz is congratulated by teammates in the dugout after homering off the Oakland Athletics' Barry Zito – one of the 541 career home runs he had before this weekend's games at Fenway Park.

OCT. 17, 2004: Big Papi celebrates his game-winning homer in the bottom of the 12th inning against the New York Yankees in Game 4 of the American League Championship Series. The win kept the Red Sox alive in the series and put them on the path to a historic comeback from a 3-0 series deficit.

Ortiz leaps into the arms of his teammates as they celebrate his 12th-inning, game-winning homer against the New York Yankees in Game 4 of the 2004 American League Championship Series. The Red Sox won, 6-4. Associated Press/Amy Sancetta

OCT. 27, 2004: David Ortiz celebrates Boston's first World Series championship in 86 years after the Red Sox defeated the St. Louis Cardinals 3-0 in Game 4 to sweep the 2004 series.

OCT. 26, 2007: Ortiz and Kevin Youkilis laugh during practice before Game 3 of the World Series at Coors Field in Denver. The Red Sox swept the Colorado Rockies in the series to win their second championship in four years.

APRIL 8, 2008: David Ortiz walks with Red Sox legend Johnny Pesky during Boston's home opener to unfurl the 2007 World Championship banner at Fenway Park.

JUNE 9, 2009: Ortiz shouts after popping up with two men on base against the New York Yankees at Fenway Park. Ortiz wasn't at his best in 2009, batting just .238.

APRIL 1, 2014: David Ortiz takes a selfie with President Obama during a ceremony an the White House to mark Boston's 2013 World Series win – Ortiz's third championship.

APRIL 22, 2015: Ortiz follows through on a home run against the Tampa Bay Rays in St. Petersburg, Fla. Ortiz had a fine season, with 37 home runs and 108 RBI, but Boston finished last in the American League East.

APRIL 26, 2016: With his farewell tour just getting started, Ortiz waves to the crowd as he's acknowledged for his final appearance in Atlanta, in a game against the Braves.