Matilda Kennedy's Flash take out US NWSL

AAP

Australian Alanna Kennedy's Western New York Flash have won the US National Women's Soccer League championship after a dramatic victory in the final over Washington Spirit.

The Matildas central defender, who played the full match in the final, lifted the trophy after the Flash won 3-2 on penalties on Sunday (Monday AEDT) in Houston.

With the game deadlocked at 2-2 after extra-time, Flash goalkeeper Sabrina D'Angelo emerged the hero, saving thee Spirit penalties in the shootout in front of 8,000 fans.

With the teams tied at 1-1 after 90 minutes, Crystal Dunn gave the Spirit the lead two minutes into extra time.

Golden Boot winner Lynn Williams tied the game for the Flash with a goal in injury-time of the second period of extra-time to send the match to penalties.

It caps a memorable season for Kennedy, with the 21-year-old making her Olympic debut in Rio following strong form in the NWSL.