Manchester United has been accused of “double dealing” after sponsorship talks between the club and a potential sponsor collapsed.

Internet gaming group Mansion condemned the bahviour of United after talks about a £70m shirt sponsorship deal broke down.

Mansion chief negotiator David Kinsman said they had verbally agreed a deal, but then United pulled out after holding talks with other firms.

The club is looking for a new sponsor to replace Vodafone, whose £9m-a-year deal ends at the end of the season.

Mr Kinsman said he had cut short a business trip in China to meet the club’s commercial director Andy Anson after being led to believe the two had “done a deal”.

“It was something of a surprise therefore to be told last night that United had been negotiating with someone else,” he added.

“During the negotiating process we had no idea this kind of double dealing was going on. Manchester United have not acted as we expected them to.”

“We are not naive businessmen by any stretch of the imagination but this has left us flabbergasted,” Kinsman said.

“This might be the way Manchester United do business but it does not suit us.

“It was indicated to us that we had done a deal. It was something of a surprise, therefore, to be told on Sunday night that United had been negotiating with someone else.

“During the negotiating process we had no idea this kind of double dealing was going on. Manchester United have not acted as we expected. We were very surprised the discussions were terminated in what we consider to be an unprofessional manner.”

The cash deal with Mansion would have been worth around £65m to £70m over the next four years.

A United spokesman said: “We would understand why anybody would be disappointed at not securing the shirt sponsorship deal for Manchester United.

“We have not and do not enter into periods of exclusive negotiation and every party we have discussed the shirt sponsorship with are aware of that. Our priority is to look for the most appropriate deal for Manchester United.

“We have been having discussions with Mansion, and we are sorry they feel that way and wish them every success in the future.”

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