Albert Pujols will lead a stacked NL roster of four first basemen into tonight’s Home Run Derby at Busch Stadium.  St. Louis native Ryan Howard along with Prince Fielder of Milwaukee and Adrian Gonzalez of San Diego will represent the National League.

Over in the American League, they were scrambling looking for representatives.  Last year’s winner Justin Morneau opted out and Josh Hamilton who put a clinic on in the first round last year was not allowed by Texas as he is just coming off the disabled list.  So, they’ll rely on catcher Joe Mauer of the Twins, Nelson Cruz of Texas and Brandon Inge of Detroit and Carlos Pena of Tampa who were late additions.  Pena is taking the place of Dustin Pedroia and Inge was voted in by fans as the 33 rd player.

Here is how the Home Run Derby works:

In the first round, each hitter has 10 outs.  The top four advance to the second round.  In the second round, totals from the first round carry over.  The two players with the highest total of HRs advance to the final.  In the championship round, both finalists start back at zero and each gets 10 outs.  The player with the most dingers wins.

If two or more players are tied after the second round, they each get five swings to break the tie.  After that, additional tie breaker rounds continue with three swings apiece.

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