Midfield star Zinedine Zidane has given Juventus yet another injury scare in the build-up to their European Champions League clash with Manchester United next week.

The twisted knee which kept France's World Cup hero out of action for three weeks before the semi-final first leg at Old Trafford flared up again at the weekend, forcing him to retire at half-time against Bologna.

"I didn't come out for the second half because the joint was giving me trouble," said the Frenchman. "I told the coach that I didn't want to go on and he agreed.

"But it's strange all the same," he admitted. "I didn't feel anything for the 90 minutes in Manchester, but here all it needed was 45 minutes to cause me problems."

However, Zidane's injury was not the only note of alarm for coach Carlo Ancelotti in Sunday's 2-2 draw.

The Italian champions took the lead through Filippo Inzaghi, but the lanky striker went on to miss a penalty as Juventus squandered several chances before letting Bologna rally to a 2-1 lead. Angelo Di Livio salvaged a draw with a late equaliser.

The performance may seem like good news for United fans, but it is probably a bad omen. With just one point from their last two games, Juventus are now mid-table and all but certain to finish outside the top four.

That means they will walk out against United on Wednesday week knowing that their only real chance of playing in the next edition of the Champions League is to win the current one.