Influential midfielders Lassana Diarra and Niko Kranjcar are, like Defoe, also under specialists' care for the injuries which kept them out of Saturday's 2-2 home draw with Hull.

And Adams, ready to select some of last season's FA Cup-winning heroes who have now become bit-part players - like Kanu, Hermann Hreidarsson and David Nugent - for the big European night, insists he will not risk the fitness of top-line stars.

Defoe has become a major concern after being substituted by England at half-time of the 2-1 win over Germany in Berlin because of an aggravated calf injury.

Adams initially hoped the £7.5million striker, whom he is desperate to keep despite the fear that bigger clubs will bid for him in the January transfer window, would be fit to face Hull.

But Adams admitted: "He's had this problem before and we've got to get it sorted out for him. We will.

"He is seeing a (specialist) guy on Monday and we'll know more about his situation then. I'm not a doctor so I can't really comment at this stage but we'll see.

"No, he won't play against Milan. And Lassana is seeing other specialists (on) Monday, Tuesday and Wednesday. So he's got to be a doubt with his ankle. We're covering all bases with them, making sure they get the best.

"Niko's come back from his specialist with a good report but he got a bang on the ankle where he had the operation (in August) and I won't take chances with anyone who is not 100% fit.

"I did that with myself as a player and you can't do yourself justice."

Adams saw his injury-hit side pegged back twice at Fratton Park on Saturday by Hull who showed just why they have commanded such a prominent place on their top-flight debut - sheer persistence.

Pompey thought Peter Crouch's header after 21 minutes and then Glen Johnson's spectacular 30-yard thunderbolt on the hour would have been enough to tame the Tigers.

But Michael Turner equalised with a header from a corner nine minutes after the break and veteran substitute Dean Windass claimed to have levelled again four minutes from the finish, although really it must go down as a Noe Pamarot own goal.

Johnson's glory was stolen after one of the most stunning strikes of the season and the right-back who starred for England in midweek admitted: "The two goals we gave away were horrific and it takes the gloss off.

"Naturally I'm happy with my goal. I hit it really sweet with my left and I know I can do that with either foot but we've all got to learn from the way we let them back in it."

Adams, yet to win at home since he took over from Harry Redknapp last month, said: "Our attitude was great but we are turning the ball over too easily and with teams like Hull, who always aim to put it back in your box, you can't afford to do that.

"That's three consecutive home games now in which late goals have cost us but at least we are still picking up points and that's three games unbeaten now which you would take in the current Premier League climate.

"Thursday is a huge game for us against Milan, a big reward for what we did last season and a great night for the fans but I'd rather we keep picking up points from games like the one at home to Blackburn next Sunday because the league has always got to be the priority."