Gordon Strachan has resigned as Middlesbrough manager after less than a year in charge at the Riverside.
Strachan departed with the club in 20th place in the Championship, their lowest league position for 20 years.
"He offered his resignation but not only that - in doing so he tore up his contract," Boro chairman Steve Gibson told BBC Tees.
"He sought no compensation and walked away from the club with empty hands and it's a measure of the man."
Gibson added: "Gordon would be the first to admit that things haven't turned out as we'd have hoped.
"We've had some long, hard very honest discussions in the last month, and today Gordon met with me, we had a long discussion and during that debate he offered his resignation, and I accepted it.
"He's a man of massive integrity, very hard-working, cared deeply for this football club.
"We asked him to do a huge job, I know he gave his best and sometimes circumstances happen where it just doesn't work.
"I like him enormously, but it hasn't worked and we had to face up to it."
The Teessiders lost 2-1 at home to Leeds on Saturday, dropping to 20th place in the Championship with six defeats in their first 11 league games.
Strachan, who won only 13 of his 46 games in charge, succeeded Gareth Southgate as manager in October 2009.
Strachan was assigned the task of building a squad fit for a return to the Premier League on his appointment, and made it clear he was ready for the challenge having left Celtic at the end of the previous season.
"I don't need to be here and I don't have to be here. I'm here because I want to be here," said Strachan on his arrival.
"When I left Celtic I told everyone close to me that it would be very difficult for me to retrace my steps in terms of the excitement there.
"I felt I had to do something different. I have a chance of something different here."
Strachan soon set about adding a Scottish spine to the Middlesbrough side, bringing in Stephen McManus, Barry Robson, Willo Flood and Scott McDonald from former club Celtic, and Aberdeen forward Lee Miller, as he surrounded himself with familiar faces.
However, by then the former Coventry and Southampton boss had endured a disappointing start to his reign, opening with a 1-0 home defeat by Plymouth, as the club drifted from fourth place in late October down to mid-table by the time they lost the final game of 2009 against Barnsley in late December.
The second half of the season saw Middlesbrough weakened by the departure of winger Adam Johnson to Premier League side Manchester City, and results continued to waver from a 2-2 derby draw with Newcastle and a 2-0 win at home to Queens Park Rangers, to defeats at promotion-chasers Blackpool, Nottingham Forest and West Bromwich Albion.
Having missed out on the play-offs last term, Strachan set to work rebuilding the side during the summer, once again turning to Scotland to sign Rangers duo Kris Boyd and Kevin Thomson, as well as Charlton midfielder Nicky Bailey and Estonia winger Tarmo Kink.
But impressive performances in beating Burnley and Reading were punctuated by a home defeat by Ipswich and a rotten run of form away from the Riverside which has seen four defeats from five matches in the Championship.
Injuries to key players including Thomson and captain Gary O'Neil dented Boro's strength, while Boyd has struggled to replicate his Scottish Premier League form in the Championship.
With dwindling crowds and a media outcry following a 'curt' post-match interview following a draw at home to Portsmouth, the final straw for Strachan came in Saturday's defeat by Leeds.
Steve Agnew has been given responsibility for all first team matters until a new manager is appointed
