Nigerian Striker Victor Anichebe struck a ferocious shot to help bottom club Sunderland to her first victory of the English Premier League Season.
Sunderland move on to five points but stay bottom because of a worse goal difference than Swansea who host Manchester United on Sunday.
Victory also ensures Sunderland will not go on to earn the tag of worst start to a Premier League league start.
Ireland international Harry Arter produced a superb long range effort inside the first five minutes but Sunderland’s young goalkeeper Jordan Pickford saved superbly.
However, he could do nothing about Gosling’s goal as he converted via his stomach a great cross by Adam Smith for his third goal of the campaign.
Pickford kept his side in the game as he pulled off another terrific stop from Joshua King who had been set up by the impressive Junior Stanislas.
Defoe teed up Victor Anichebe and he turned smartly in the area holding off Simon Francis and fired the ball past Artur Boruc.
Sunderland’s tails were up and a fine sweeping move involving Anichebe and Defoe led to Paddy McNair whipping in a cross which was turned in by Duncan Watmore only for it to be ruled out for offside.
Sunderland continued in the same vibrant form in the second-half only for their momentum to be halted as Pienaar was sent off for a second bookable offence.
Pickford then prevented the Cherries taking the lead as he denied England midfielder Jack Wilshere a goal on his 100th Premier League appearance.
However, the game swung back in Sunderland’s favour when Smith brought down Anichebe and Defoe slotted home the resulting penalty with 16 minutes remaining and ending Boruc’s run of three saved spot kicks.
Bournemouth threw everything at the Sunderland defence, substitute Benik Afobe should have done better on two occasions whilst Pickford once again came to his team-mates’ aid with a stunning save from Joshua King at close range.
Anichebe becomes only the third different player to score for Sunderland this season, and his start today was his first of the season.