There was a feeling that the 36-year-old Ivorian was well past his best and that returning to Stamford Bridge might tarnish the legacy he left after a dazzling first spell with the Londoners.
Drogba has, however, well and truly silenced the doubters in the last week, scoring three goals in three games and proving a more than capable understudy for the injured Diego Costa and Loic Remy.
"His character is bigger than his body," Mourinho told reporters after the centre forward grabbed the opening goal in Tuesday's 2-1 League Cup fourth-round victory at Shrewsbury Town.
"What he did today maybe was because of his character and not because of his body. Let's see the reaction after this but this is what makes players special.
"If I was a kid player and I played with this guy on my side, what more could I wish for For the kids it must be a privilege and they have to learn by example -- the example the older guys gave today."
Drogba left Chelsea two and a half years ago after helping them win the Champions League for the first time.
He joined the Blues from Olympique Marseille in 2004 and scored 157 goals in 342 appearances in his first spell, hoovering up three Premier League titles, four FA Cups and two League Cups.
Drogba was on target from the penalty spot in the 6-0 romp against Slovenians Maribor in the Champions League last week and also struck with a trademark header in the 1-1 draw at Manchester United in the Premier League on Sunday.
Premier League leaders Chelsea rested several first-choice players at fourth tier Shrewsbury and Mourinho said it was the senior professionals who carried his team through to the quarter-finals.
"The message I want is the message Didier, Filipe Luis, Oscar and Gary Cahill gave -- doing something they shouldn't be allowed to do but they did, which is play two football matches in 48 hours," said the manager.
"They were fantastic. I had people like Petr Cech and John Obi Mikel, people with lots of years at the club, who would prefer to start the game at Old Trafford. They didn't and they came here today and gave a fantastic example.
"After that there are the young boys and they have to follow the spirit and the professionalism of the others," added Mourinho.
The Portuguese seemed to indicate he was less than satisfied with the performance of his younger players at Shrewsbury.
"I expect people that have not been playing a lot to raise their level and create problems," said Mourinho. "I love problems of choice but it's easy to choose my team for Saturday."
Next up for Chelsea, who have a four-point lead at the top of the Premier League, is a home derby against second from bottom Queens Park Rangers at the weekend.