Manchester United have stumbled to a home draw in their Europa League opener with FC Twente. (AP PHOTO)

Christian Eriksen has followed a ferocious finish with a costly mistake as Manchester United began the Europa League with a 1-1 draw against Erik ten Hag’s former club FC Twente.

This was a continental campaign few expected the Red Devils to be embarking on having missed out on European qualification through the Premier League last term.

But May’s shock FA Cup triumph against rivals Manchester City secured United a Europa League spot and they opened the new-look league phase in frustrating fashion against the Eredivisie side.

United boss Ten Hag spent a combined 23 years at Twente across three stints as a player and then in different coaching capacities, saying on the eve of the game: “It’s not nice to have to hurt something you love.”

Eriksen’s first-half rocket put United on course to do just that, but the lowest-ranked side, in terms of UEFA’s coefficient, heading to Old Trafford in this revamped group phase had other ideas.

Sam Lammers went close with an early strike and was not to be denied a famous goal, dispossessing Eriksen as the midfielder turned into danger and then all too easily beating Andre Onana in the second half.

“You saw that was the game of their life. They fought for every yard and we didn’t,” Ten Hag, who saw his side score just one of their 18 attempts, said.

“99 per cent is not enough, You have to give 100 per cent. You have kill the game. You have to finish it off.

“When you have ambition, then you have to perform, then you have to prove that point.

“Today, especially in the second half, I think we were too easy-going, too complacent.

“We have to be more clinical in such situations, but I don’t think that was the only problem.

“It’s also a question of mentality, and kill it off, make the second goal, and then the game is over.”

Elsewhere on Wednesday night, Norway’s Bodo/Glimt beat two-time European Cup champions FC Porto 3-2 and Dutch side AZ Alkmaar won by the same score at home to Sweden’s Elfsborg.

Serie A side Lazio triumphed 3-0 against Dynamo Kyiv in neutral Hamburg, Hoffenheim drew with FC Midtjylland in Denmark and it was also 1-1 between Nice and Real Sociedad in the south of France.

Anderlecht defeated Ferencvaros 2-1 in Brussels, while Galatasaray beat PAOK 3-1 in Istanbul and Slavia Prague won 2-0 at Bulgaria’s Ludogorets.

Like the Champions League, the second-tier European competition has a new format and 36 teams instead of 32. It features a league system in which each team plays eight games against different opponents, replacing the old group stage.