Christian Eriksen transforms from hero to villain as Manchester United are held to a Europa League tie.

Manchester United began the Europa League with a 1-1 draw against Erik ten Hag's previous club FC Twente, with Christian Eriksen making a costly mistake after a vicious finish.

After missing out on European qualification through the Premier League last season, the Red Devils were not anticipated to embark on a continental campaign.

But May's surprising FA Cup victory over opponents Manchester City secured United's Europa League spot, and they began the new league season in frustrating fashion against the Eredivisie side.

Ten Hag, United's manager, spent a total of 23 years at Twente, three as a player and later in various coaching capacities, remarking on the eve of the game: "It's not nice to have to hurt something you love."

Eriksen's first-half rocket set United on track to achieve exactly that, but the bottom-ranked team in terms of UEFA coefficient heading to Old Trafford in this revised group round had other plans.

Sam Lammers came close with an early effort and was not to be denied a memorable Old Trafford goal, dispossessing Eriksen as the midfielder became a threat and then comfortably beating Andre Onana in the second half.

Twente's largest European travelling support went berserk and made themselves heard well before kickoff, even chanting Steve McClaren's name as their title-winning ex-manager was unveiled.

Sir Alex Ferguson assisted in presenting a gift to his former assistant, as McClaren had recently concluded his most recent term with United, and the Jamaica manager had observed his former clubs' intense start.

Twente manager Joseph Oosting voiced confidence on Tuesday that his squad might damage United, after Lammers almost gave them a memorable lead in front of the Stretford End.

Bart van Rooij dispossessed the dithering Diogo Dalot in the corner and fired in a low cross to the near post, where the forward's shot sailed just across the face of goal with eight minutes remaining.

Twente's strong, confident start continued, as United were undone by a combination of last-ditch defending and poor decision-making.

In actuality, the first shot on Lars Unnerstall's goal came from a Twente player's boot, and the goalkeeper had to be alert to prevent Mees Hilgers' clearing from flying into the upper corner.

United did not get a shot on goal until the 35th minute, and there was little Unnerstall could do.

After Dalot was closed down, the ball drifted free in the box, and Eriksen reacted quickly, unleashing a powerful first-time strike beyond Twente's goalie.

Marcus Rashford was active both before and after his goal, and Harry Maguire had a chance from a corner saved early in the second half.

However, United's dominance had relaxed, and Onana came down low to prevent a 30-yard Sem Steijn free-kick from crossing the line in front of Twente's 4,000 or so spectators.

The visitors smelled blood and caused havoc in the 68th minute.

Van Rooij's powerful run from deep within his own half was eventually halted in United territory, only for Eriksen to become a danger. Lammers got the ball off his toes, moved forward, and easily beat Onana at the near post.

United battled desperately to recover from the gut hit.

Joshua Zirkzee was rejected, Bruno Fernandes went off target, and Alejandro Garnacho curled over.

Penalty appeals when Kobbie Mainoo went down were denied, and Twente survived penalty-box melees in extra time.