Paddy Jackson is "keen to get on with business in a London Irish shirt" according to coach Dec Danaher.
Former Ulster fly-half Jackson joined the Exiles after a season at Perpignan in time for their Premiership return.
But Jackson's signing has also attracted unwanted attention for Irish, following his acquittal of rape after a high-profile trial in Northern Ireland.
"Paddy has come in and worked hard and we're looking forward to seeing what he can do," Danaher told BBC Sport.
"What's happened has happened and, as coaches and players, we're concentrating on the task ahead."
Jackson, 27, had his contract with the Irish RFU terminated in April 2018 in the wake of the 42-day trial.
He and team-mate Stuart Olding were acquitted, but were sacked over messages exchanged via text and social media, which were revealed in court.
Following news of Jackson's arrival at Irish two of the club's sponsors, including drinks giant Diageo, decided to end their support.
On the pitch, Jackson will be reuniting with former Ireland head coach and now Irish director of rugby Declan Kidney as well as Les Kiss, his former head coach at Ulster and Ireland.
Danaher, Irish's assistant coach, says Jackson has settled in well alongside other new recruits.
"Paddy's part of us working towards what will hopefully be a successful return to the Premiership," Danaher said.
"He's spent a year in France before coming here. He seems a little bit more at home and I think he's glad to be back in an English-speaking country.
"He's a quiet lad who works hard on the training pitch and he's just keen to get on with his business."