Gonzalo Higuain is in final negotiations to move to Chelsea, but it is "impossible" the Argentina striker will feature against Tottenham on Thursday, Blues boss Maurizio Sarri says.
Higuain has been on loan at AC Milan from Juventus this season, scoring just once in his last 12 appearances for the Rossoneri.
But his record of 36 goals in 35 Serie A games in his one season at Napoli under Sarri, 2015-16, has persuaded Chelsea to compromise on their usual policy of not signing players aged over 30 for vast sums.
It is thought the initial deal will be on loan until the end of the season, with further options.
"I know they're a few hours into signing a contract today," Sarri said.
Chelsea play Tottenham in Thursday's Carabao Cup semi-final second leg at Stamford Bridge, bidding to overturn a 1-0 deficit to reach the February 24 final.
The Blues had until 12 oon to register Higuain for the match, but Sarri says Higuain will not be involved.
"For tomorrow, I think, it's impossible," Sarri added.
For Chelsea to amend their policy and sign Higuain is a show of faith in Sarri, whose hopes of a long-term future could depend on the former Real Madrid striker's goals.
Higuain has just eight goals this season, one fewer than Alvaro Morata, who is now expected to leave Stamford Bridge.
"I think the club agree with me when I told them my opinion about the team," Sarri added.
"It's very difficult in January to find one of the most important strikers in the world. So I think the club is working very well because it's not easy to get a new striker.
"We hope he'll bring goals, that he starts scoring for us. He's also very good at other aspects, other than just goals, but that's what we are hoping for.
"He has had some difficulties recently, but we're hoping we can raise him back to his best form."
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