His fitness for Wednesday's match in London is key for the Italians, who trail 1-0 from the first leg and are stretched in midfield due to injuries to Andrea Pirlo and Massimo Ambrosini, Mark van Bommel's ineligibility and Gennaro Gattuso's ban.
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"The (team's formation) depends on Boateng who has a good chance to play," Milan coach Massimiliano Allegri told a news conference.
"And if he does, we still have to decide if his position would (be) in the centre of midfield or on the right side. But the rest of the team is picked."
Clarence Seedorf, likely to be selected in a makeshift midfield, said even though Boateng had missed the defeat in Milan, the outcome of his fitness test would not be on the team's mind as they sought to overturn the deficit.
"We lost the last match without him. I don't think it is one player that will make the difference," the 34-year-old said.
"It is always a team effort and even if he has great individual qualities it still would be the team that will make the difference, that we have to worry about."
The Dutchman said the Serie A leaders had a vital weapon in Sweden striker Zlatan Ibrahimovic.
"I can just tell that we have one of the best strikers in the world in our team and that it is up to the team that he also can perform well," he said.
Seven-times European champions Milan have given themselves a tough task after allowing Spurs to grab an away goal in a fiery first leg three weeks ago that was marred by Gattuso's post-match clash with Tottenham assistant coach Joe Jordan.
The Italians are buoyed up by recent domestic wins over Chievo, fellow title contenders Napoli and arch rivals Juventus and Seedorf was hopeful their good run would spill over into the European campaign.
"We respect Tottenham," he said. "They have shown themselves to be a good team so we know what to do tomorrow."
