Jonathan Woodgate was 'disillusioned' with the pace of Middlesbrough's Premier League progress, manager Gareth Southgate has revealed.
Just 17 months after signing for his hometown club, the England defender moved to Tottenham during the January window in a deal worth in the region of £7million.
The transfer paid dividends almost immediately when he scored the winning goal in the Carling Cup final at Wembley as Spurs beat Chelsea 2-1.
But as the cash was used to help fund the club-record capture of striker Afonso Alves, Boro have also declared themselves happy with the overall outcome.
Looking back at the politics behind the move ahead of Woodgate's first appearance against his old club since leaving, Southgate said: 'You've got to believe the decisions you make are right for the club and right for the player.
'At the time he left we said openly that Jonathan was disillusioned here.
'He got the opportunity to go and do what he wanted to do and that in a sense has been justified by picking up a trophy as quickly as he did.
'I certainly don't sit there and hope it doesn't work out for Jonathan because he was very important and did a great job for us. You want him as an individual to go on and achieve what he should achieve.'
Asked to expand on the reasons for Woodgate's disillusionment, Southgate added: 'I think as a player you always want immediate success and we had a struggle at the start to the season.
'It's been a difficult season for everybody. Emotionally it's been a draining season because in almost every game there's been just one goal in it.
'As a player, if you've been at a club like Real Madrid and you've come here and you're not challenging for trophies and you're not challenging for Europe then that can be difficult to come to terms with.
'Jonathan wanted his challenges to be at the other end of the table. I can understand that, he's been involved in the international set-up and he wants to play his football at the right end of the table.
'We all want to do that as well but our younger players have got time to get there, he perhaps felt he needed to that a bit more quickly.
'We've got a plan of what we want to do and unfortunately the timescale of that didn't fit in with what Jonathan wanted.
'I've got no bitterness about that at all, those were facts at the time, the deal was right for us and the club for him to move on and, with the players coming through, we've been able to perform at a high level despite him going. He's got a medal that he wouldn't have had and it's worked out for everybody.
'I wouldn't have wanted to let a player of that quality go without having somebody coming in and making an impact and strengthening an area of the field we felt needed strengthening.'
As Southgate points out, Woodgate's greatest legacy at Boro was the club's survival in the Premier League last season.
Signed just days after a 4-0 home defeat to Portsmouth in August 2006, the former Leeds and Newcastle defender shored up a creaking backline.
His performances earned him an England recall and he was able to put behind him the injury nightmare that had ruined his spell at Real Madrid.
Southgate added: 'Jonathan was good for us and I think we were good for Jonathan.
'We got him back on track with playing nearly a full season. I think our medical team played a huge part in that and he played a massive part for us as well.
'His performances alongside Pogi (Emanuel Pogatetz) quite possibly mattered as much as the goals from Mark Viduka and Yakubu. That was a relationship that was beneficial both for us as a club and for him.'