Mourinho missed Inter's last three league games, including Friday's 3-1 defeat at Catania, after serving a touchline ban.

Inter claimed just one win in those games and Moratti believes Mourinho's return will be a huge boost in confidence for his side ahead of their Champions League crunch game at Stamford Bridge.

"Mourinho is a guarantee," said Moratti to Gazzetta dello Sport. "To see him on the bench makes me clam.

"I'm certain Mourinho will pick the best possible team and that the Inter players will show heart and character on the pitch."

The Serie A giants go into tomorrow's return leg in London holding a 2-1 advantage over Chelsea.

Moratti insists whatever happens tomorrow, Mourinho will remain at Inter next season.

The former Chelsea boss has been linked with a move to Real Madrid this summer but is under contract with the Nerazzurri outfit until June 2012.

"We have an excellent rapport and reciprocal admiration," said Moratti. "No external criticism can ruin that or distance him (Mourinho) from Inter."