The strained relationship between Stewart Downing and Middlesbrough was heading for an irrevocable breakdown last night after the winger submitted a written transfer request that was swiftly rejected. He cited a lack of ambition from his home-town club as the driving force behind his decision.

Despite signing an improved five-year contract worth in the region of £50,000 a week in February last year, Downing has ignored warnings from Gareth Southgate, the manager, that with the team only two points off the bottom of the Barclays Premier League, now would not be a good time to be seen to be engineering an exit.

Downing’s request was rebuffed by Steve Gibson, the chairman, leaving the England player in an increasingly isolated position in his efforts to secure a transfer to Tottenham Hotspur. The North London club had an opening bid of £6 million dismissed as derisory by Middlesbrough, who have also turned down a second bid, believed to be worth about £12 million.

“If they think it is derisory, then fair enough,” Harry Redknapp, the Tottenham manager, said. “I know \ been back and made a fantastic offer. If they don’t want to sell him, end of story.”

Keith Lamb, the Middlesbrough chief executive, said: “Prior to receiving the transfer request, we received an improved offer for Stewart from Tottenham. We immediately rejected this offer and informed Tottenham that Stewart Downing is not for sale and any further interest they have in the player will not be entertained.”

The player’s father, Stewart Downing Sr, attempted yesterday to justify the request, claiming that the Teesside club had failed to fulfil promises made when his son signed his improved deal last year. “Stewart’s been frustrated since the summer,” he said. “When he signed his new contract, he was assured that there would be significant investment in the squad.”

Downing is likely to receive a frosty response from supporters if he is involved when Sunderland visit for a Premier League match on Saturday. “Stewart’s thought long and hard about the decision to hand in a transfer request,” the player’s father said. “He hopes the fans will understand his reasons for doing so.”