David Ortiz’ teammates call him “Cooperstown,” and were there any doubts over his Hall of Fame worthiness before the 2013 postseason, he is dispelling them with a vengeance. Already universally hailed as the greatest designated hitter of all time, and long ago declared the greatest clutch hitter in Red Sox history, Ortiz is making a bid to be recognized as one of the greatest World Series performers ever, too. That’s a lot of superlatives for one player. Add them all up, and they equal immortality in the New York hinterlands. What Ortiz is doing to the St. Louis Cardinals this World Series is historic. What might be a surprise to fans, even Red Sox fans, is that it’s nothing new. Ortiz enters tonight’s Game 6 at Fenway Park batting .733 with a .750 on-base percentage, 1.267 slugging percentage and 2.017 OPS. Not surprisingly, all rank in the top six all-time for a single World Series. But consider Ortiz’ lifetime numbers and ranks in those categories. His .465 average in three World Series is fourth all-time behind Phil Garner (.500), Amos Otis (.478) and Barry Bonds (.471), and Ortiz has nearly twice as many plate appearances (54). The OBP of .556 trails only Bonds (.700 . . . seriously?) and Garner (.571). The slugging percentage (.814) is fifth. The OPS (1.370) is fourth. Unlike the great New York Yankees of the 1940s and ’50s, Ortiz won’t get a dozen cracks at the World Series, so he won’t rate on the home run (three) or RBI (14) charts. It also doesn’t help his cause that the Red Sox swept their first two trips in 2004 and ’07, meaning his production has come in only 13 games. But when one balances his regular-season numbers and his postseason ones, it’s hard to miss that he’s been at his absolute best on the absolute biggest stage. And that right there? That’s a Hall of Famer. “What planet is that guy from?” catcher David Ross asked after a Game 5 that saw Ortiz go 3-for-4 with a RBI double, his only out a 370-foot missile to dead center. The Cardinals have had no answer for Ortiz. St. Louis manager Mike Matheny could practically be heard throwing his hands in the air during a conference call yesterday when asked how to approach the slugger. “If you’ve got any suggestions for me,” Matheny said, “I’m all ears.” Ross and the rest of Ortiz’ teammates are simply marveling. “At this point, it’s pretty tough not to sit in the on-deck circle and be a spectator,” left fielder Jonny Gomes said. “This guy, he’s making the game seem pretty easy.”