Mancosu's two goals guide Impact past DC United

United in an Eastern Conference knockout-round match on Thursday.

Laurent Ciman added his first goal since the 2015 regular season to open the scoring early. Ignacio Piatti also scored late for fifth-seeded Montreal, who advance to the conference semi-finals for the second consecutive season.

The Impact will begin the two-leg semi against the New York Red Bulls at Montreal's Stade Saputo on Sunday. The return leg will be played in Harrison, N.J., on Nov. 6.

Lamar Neagle and Taylor Kemp scored in the dying moments for fourth-seeded D.C.

Mancosu, who only joined Montreal on loan from Italian side Bologna in July, made it 3-0 in the 58th minute with his second goal of the game.

Ambroise Oyongo got free on the left and with little defensive pressure sent in a cross toward Mancosu near the penalty spot. Mancosu's flick-on header skipped off the ground and beat goalkeeper Bill Hamid inside his right post.

With United sending players forward, Mancosu set up Piatti for Montreal's fourth goal on an 83rd-minute counterattack.

Patrick Nyarko assisted on Neagle's 90th-minute consolation strike, and Kemp scored on a long-range effort in second-half stoppage time. (Compiled by Peter Rutherford)