Matteo Mancosu scored in the second half as the Montreal Impact beat the visiting Red Bulls, 1-0, on Sunday in the opening match of their M.L.S. Eastern Conference semifinal.
The second leg of the semifinal, a two-match, aggregate-goals series, is next Sunday at Red Bull Arena. The Red Bulls will be without forward Omer Damari, a substitute who received a red card in injury time after a hard slide into Calum Mallace.
“At times we played well and were organized, and then one play cost us, even though we had pretty good control of the match,” Red Bulls Coach Jesse Marsch said.