Substitute Talles Magno scored in the 88th minute and visiting New York City FC rallied to reach their first-ever MLS Cup final with a 2-1 victory over the Philadelphia Union on Sunday afternoon.

Magno -- who scored only twice in the regular season -- helped NYCFC defeat Philadelphia in the Eastern Conference Final on a day they were without MLS Golden Boot winner Valentin Castellanos due to a red-card suspension.

Castellanos will be able to return for the final in Portland, who defeated Salt Lake in Saturday's Western Conference title game.

Maximiliano Moralez also scored for fourth-seeded City, which prevailed over No. 2 seed Philadelphia after advancing past Supporters' Shield winners and top-seeded New England on penalties in the semifinals.

Union leading scorer Kacper Przybylko helped pressure NYCFC into an own goal to give Philadelphia a lead that lasted less than two minutes.

COVID-19 protocols ruled 11 players out for the hosts, who were forced to make six changes from the starting lineup of their semifinal triumph on penalties over No. 3 seed Nashville City SC.

Only seconds after the restart following Philadelphia's 63rd-minute goal, New York's Maxime Chanot drove a speculative effort from distance that wrong-footed Matt Freese into an awkward save.

Magno got a piece of the rebound before it eventually fell to Moralez at the back post, who hammered a powerful finish past Freese.

Freese redeemed himself with an excellent save of Alexander Callens' deflected header, and the Union could've gone ahead again in the 87th when Nathan Harriel flashed a header over the bar.

Instead, minutes later Gudmundur Thorarinsson seized upon a mistake from defender Olivier Mbaizo to work free inside the left side of the penalty area. From there, he drove a firm cross to the sprinting Magno, who hammered a first-time finish past Freese.

Philadelphia took the lead when Leon Flach and Jamiro Monteiro combined to work out of pressure, before Flach drove an inswinging cross toward Przybylko near the center of the penalty area.

Callens reached out his leg to try to keep Przybylko from reaching the service. He succeeded, but at the expense of turning it into his own goal beyond the dive of goalkeeper Sean Johnson.