Wallaby flyhalf O'Connor in doubt for England series and will miss Super Rugby Pacific playoffs

Injured playmaker James O'Connor is expected to be sidelined for a month, ruling him out of Queensland's Super Rugby Pacific finals campaign and racing the clock for the Wallabies Test series against England.

O'Connor was on Monday diagnosed with a low grade hamstring tear after suffering the injury during the second half of the Reds' 34-22 victory over the last-placed Moana Pasifika on Friday night.

The 30-year-old had only returned the week previously from a knee injury with his absence keenly felt by the Reds, whose season went off track with a four-game losing streak.

The undermanned Queensland now face an even tougher prospect to travel to Christchurch to take on the Crusaders in the final round clash on Friday night.

Sitting seventh, they may also meet the Crusaders at Orangetheory Stadium again in the quarter-finals the following weekend.

Another scenario would see the Reds take on the Brumbies in Canberra in week one of the play-offs.

Queensland say O'Connor is an outside chance to return for the semi-finals or final should they make it that far.

The Reds have battled a torrid injury toll with fellow Wallabies stars Hunter Paisami and tighthead prop Taniela Tupou in the casualty ward.

Centre Josh Flook dislocated his shoulder against Moana Pasifika.

Loose forwards Harry Wilson and Fraser McReight as well as cross-code winger Suliasi Vunivalu have also spent time on the sidelines.

Wallabies coach Dave Rennie, who was in the stands at Suncorp, will name his 36-player squad in two weeks.

Brumbies five-eighth Noah Lolesio, who himself has battled some injuries, is healthy again and has found form to help steer his third-placed team into the finals.

He and Quade Cooper will likely vie to wear the Wallabies No.10 jersey in the opening Test against England on July 2 in Perth if O'Connor is unable to prove his fitness.