Fabian Espindola atoned for a missed penalty by netting the winner as DC United came from two goals down to beat Philadelphia Union 3-2 at the RFK Memorial Stadium.

The 30-year-old made amends for a disappointing first-half penalty by heading home a 79th-minute winner as Ben Olsen's side stunned Philadelphia this morning.

Visiting coach Jim Curtin could have hardly wished for a better start in Union's trip to the capital as they raced into a 2-0 lead inside four minutes.

First, CJ Sapong tapped home inside 60 seconds, before Sebastien Le Toux doubled the advantage with an angled effort, with a deflection deceiving goalkeeper Andrew Dykstra.

The hosts slowly but surely developed a foothold and Espindola rifled his effort just wide of the post on 16 minutes, before suffering a worse miss shortly after the half-hour mark.

Davy Arnaud drew a foul from Raymon Gaddis inside the penalty area, but Espindola blazed the resulting spot kick over the bar to compound United's woes at the break.

However, Alvaro Saborio threw his side a lifeline by squeezing a first-time volley past Brian Sylvestre to mark his debut with a goal and renew the hosts' belief heading into the break.

On 66 minutes, the comeback was complete when Nick DeLeon tapped home a rebound from close range after Sylvestre fumbled Espindola's tepid long-range attempt.

Not content with drawing level, United went in search of a winner and it came 11 minutes from the end as Espindola redeemed himself by heading home Chris Korb's cross to snatch the victory.