Quade Cooper was stretchered off Ballymore with a neck injury as the Melbourne Rebels produced a shock 18-13 trial upset of the Queensland Reds on Friday night.
Cooper suffered a jolting hit from behind in the final minute of the match to bring a long halt to play and hush over the ground as a dozen medics and officials tended him.
The Wallabies playmaker allayed some fears of a serious injury in the dressing room but was to undergo scans as a precaution and is in doubt for next week's Super Rugby opener against the Brumbies in Canberra.
Coach Richard Graham dismissed any concerns about concussion which would almost certainly sideline him for round one.
"He's all right," said Graham.
"I had a chat to him and he's in good spirits but it (scans) is one of those things we have to do.
"My expectation is that he will (play the Brumbies). He's come off, he's alert, he's talking, he's disappointed."
The incident happened just after Cooper off-loaded in his own quarter and suffered a jolting tackle from behind.
"He was facing away from where the ball was and someone has got him with a shoulder in the middle of the back," Graham said.
The injury left a pall over the final pre-season encounter and took attention away from the vastly-improved Melbourne outfit.
The Rebels, who beat NSW and the Hurricanes in the past fortnight, completed a pre-season sweep with the two-tries-to-one victory after fighting back from 13-0 down midway through the first half.
New coach Tony McGahan has worked overtime at toughening the Melbourne squad and game and it showed in their defensive and breakdown ferocity.
The Rebels also showed good signs in attack with young playmaker Bryce Hegarty outshining Cooper.
All Black recruit Tamati Ellison completed a full game in the centres but another former Kiwi, Australia-born prop Toby Smith, had the biggest impact, including a number of big hits.
Despite the Rebels' willing defence and intensity at the breakdown, the home side jumped to a 13-0 lead after 20 minutes when Liam Gill chipped ahead under pressure for Will Genia to score.
But it only sparked the Rebels fightback as Hegarty exploited the lack of Reds defensive cover with a perfect grubber for Angus Roberts to dot down.
Hegarty landed the conversion from the sideline before taking a quick tap and showing a clean pair of heels for field position that led to a penalty goal and a 13-10 scoreline.
In the best backline move of the first half, the Rebels sent Tom English away down the left wing and he powered over the top of an out-of-sorts Lachie Turner for Scott Fuglistaller to score and give his side a surprise 15-13 halftime lead.