Luciano Spalletti hailed Lautaro Martinez after the striker's first goal for the club set up a 2-0 Serie A home win against Cagliari.
With Mauro Icardi rested for Wednesday's Champions League trip to PSV, Martinez started alone up front and opened the scoring with an early header.
Cagliari had a leveller ruled out for handball following a VAR review and Matteo Politano's late volley secured a third straight league win.
Spalletti's rotation paid off as Inter maintained their momentum and the coach was thrilled with the latest sign of Martinez's development.
"He is a very strong player," Spalletti told DAZN. "He can turn in the traffic of the defenders with great ease, has insights, ability to go to the box.
"Training with Mauro he has learned something. Martinez has character, technique, leg strength, shooting, of course.
"Maybe he's a bit selfish because he did not pass the ball on one occasion and he ended up alone and then he lost it, but a little bit of selfishness does not hurt.
"He and Icardi are very good friends, and they are also very sensitive guys."
Icardi was not the only star name to be benched for Saturday's Serie A game, as Croatia internationals Ivan Perisic and Marcelo Brozovic were also left out of the starting XI.
Martinez took his chance to shine, with Roberto Gagliardini also impressing in midfield, much to the delight of the Inter coach.
"I'm always satisfied when I win," Spalletti said. "I want to use every minute of my life to improve our behaviour as a part of Inter.
"These players allowed me to make an important turnover to have some fresh players play in the Champions League.
"When you have a large squad with this much quality, you can choose a whole new 11 every few days and that is important."
