Goalkeeper Adam Kwarasey admits his Portland Timbers side must dig deep to retain their MLS Cup title this season.

The Timbers defied all odds to win their first-ever national championship last season at the expense of Columbus Crew SC.

Kwarasey was one of the outstanding performers for the Portland-based side on his debut season.

The Ghana international wants his teammates to forget about the past and focus on repeating the glory again.

“I mean it’s a new season. What we did last year is over now. As a player you always want to win," Kwarasey told the club’s official TV channel.

"Because we won it last year doesn’t mean that I am fine with not winning it this year.

"So, I am ready for the season and I want to repeat it."

Portland Timbers open their season with a home game against Columbus Crew on Sunday.

Watch Adam Kwarasey and Timbers players reflect on how winning 2015 MLS Cup prepares them for 2016.