The Dublin-born defender spent nine years at the Reebok Stadium, where he previously worked under Allardyce, and believes his current form for West Ham, he scored the equaliser against Stoke to earn his side a draw last time out, is largely due to the faith his manager has shown in him.
"I owe him everything, O’Brien told The Sunday Times. "He played me in the Uefa Cup as a kid. It was a major thing for him because Bolton had never played in Europe before. So he put a lot of trust in me.
|14/1||West Ham are 14/1 to beat Tottenham 1-0 with William Hill|
West Ham have surprised many with their early season form, the Hammers currently sit in seventh place after 12 games, and visit Tottenham on Sunday knowing a win would see them move above Arsenal and Everton in the table.
"You want to be involved in these big games," added O'Brien.
"Last season when things were a bit sticky, we had these meetings where we asked ourselves where do we want to be and who do we want to play against. These are the weeks you want to have."