VIDEO: Phillies' Altherr notches 1st inside-the-park grand slam since '99

Though the Philadelphia Phillies haven't so much as entertained the possibility of postseason contention in months, the rebuilding club still produced one of September's most memorable moments Friday night in Washington.

Aaron Altherr, who joined the Phillies in mid-August, became the first player since 1999 to record an inside-the-park grand slam when he emptied the bases (before circling them, himself) in the third inning of his club's series opener against the Nationals.

(Courtesy: MLB.com)

Altherr, with some help from Nationals center fielder Michael Taylor, became the first Phillies player to collect an inside-the-park homer since Jimmy Rollins on July 31, 2012, also at Nationals Park. The last player to tally an inside-the-park grand slam, though, was Randy Winn, who accomplished the feat as a member of the Tampa Bay Devils Rays on the final day of the 1999 campaign.

He didn't stop there, though. In the top of the fifth inning, Altherr cranked a one-out solo shot over the wall in left field, affording his club a 5-1 lead while becoming the first player to notch an inside-the-park homer and smack another one over the fence in the same game since 1987.

Altherr's big night lifted the Phillies to an 8-2 victory that further compromised the Nationals' postseason hopes. Heading into Friday's contest, the erstwhile division favorite had just a .1 percent chance of making the playoffs.