Northampton kept up their impressive early-season form and push for the Aviva Premiership title by battling past London Irish at the Madejski Stadium.
Full-back James Wilson crossed for Saints in the first half and fly-half Stephen Myler kicked 14 points as they made it five league wins from seven matches with a 19-14 success.
Wing Sailosi Tagicakibau grabbed the Irish try with number 10 Ian Humphreys adding his side's extras with the boot.
All eyes were on controversial Australian James O'Connor who took centre stage for his Irish debut just a few days after signing a contract until the end of the season.
The versatile 23-year-old Queenslander, who has amassed 223 points in 44 caps for the Wallabies, took his bow at full-back and impressed throughout with his running skills as he seeks to rebuild his career following a series of off-field misdemeanours.
He was on his best behaviour on Sunday, claiming an assist for the Exiles' try and looked poised and controlled throughout.
O'Connor was in the thick of the action from the start with a pass which almost put wing Topsy Ojo in for a try. But he was powerless to stop Saints from taking the lead as a Myler penalty pushed them ahead after Irish infringed at a ruck.
Humphreys replied for the hosts after Northampton were guilty of illegally playing the ball on the ground at a ruck.
Myler regained the lead for Saints with a penalty which deflected over off the inside of the right post and Wilson raced over for the opening try, cutting in off the right wing and taking a reverse pass from George Pisi in his stride to go over the line virtually untouched.
Myler converted and added a further penalty as Saints showed no signs of missing their England contingent of Dylan Hartley, Courtney Lawes, Tom Wood, Lee Dickson and Ben Foden.
Humphreys slotted home a three-pointer in between Myler's conversion and third penalty success and Irish suddenly found an extra gear on the stroke of half-time with quick ball from a ruck being swept along the line and O'Connor's final pass to Tagicakibau put the wing over for a fine try.
Trailing 16-11 at half-time, Irish were right back in the contest. However, they failed to build on that promise and they were unable to force their way over in the second period despite a dogged effort.
O'Connor showed his class and skill with a silky run through the Saints defence before being stopped in his tracks. Humphreys missed a difficult penalty chance but succeeded with his next effort to close the gap to just two points.
However, Myler responded in kind with his own penalty and Irish's late pressure - with one move lasting 25 phases - failed to break the Saints resolve.