Left-back bother for Inter & Chelsea
Mourinho won two Premier League titles as manager of the London club while the two sides are very similar in style.
The determination the Portuguese installed at Chelsea before leaving in 2007 is also in plentiful supply at Inter, as shown by Saturday's 0-0 draw with Sampdoria where the Serie A leaders had two sent off in the first half but had the better chances.
Chelsea were also under pressure at Wolverhampton Wanderers on Saturday but still dug in for a 2-0 victory to extend their lead at the top of the Premier League to four points.
The playing staffs have various similarities too.
Chelsea's Petr Cech and Inter's Julio Cesar, set to be fit after a minor car crash, are among the world's best goalkeepers.
Both defences are top-class although left-back is a problem with Cristian Chivu and Davide Santon injured for Inter while Chelsea's Ashley Cole and Yury Zhirkov miss out and Paulo Ferreira is not registered for the Champions League.
Midfielder Javier Zanetti will fill in for the Italians with fellow right-footer Branislav Ivanovic poised for the visitors.
"For the characteristics of our opponent, their physical nature and intensity of their play, I would really need Zanetti in midfield," Mourinho, banned for three Serie A games for his latest bout of outspoken behaviour, told reporters.
"If Santon isn't there and Zanetti plays at left-back, already the team is different to the one I had in mind."
A rock solid bank of three midfielders characterises each team and both boast two of the best playmakers in the business.
Frank Lampard, back from a virus, almost moved with Mourinho to Inter but remains the fulcrum of the side while Wesley Sneijder is probably just edging the England player in terms of form this term after a superb first six months in Italy.
But Chelsea look better up top with Didier Drogba outscoring fellow African player of the year nominee Samuel Eto'o.
The Cameroonian has had form and fitness problems since joining Inter from Barcelona in July and is not assured a start on Wednesday given Diego Milito and Goran Pandev's consistency.