The Cameroon forward joined the Genoa outfit from Everton during the winter transfer window and has had a difficult few weeks at the club.
After coming on as a substitute on his Samp debut in a 5-1 defeat to Torino, Eto’o skipped a mandatory training session that infuriated Mihajlovic.
Eto’o did play in last weekend’s 1-1 draw against Sassuolo but failed to make an impact.
“Eto’o knew that he made a mistake and he apologised,” Mihajlovic told Gazzetta dello Sport. “Everyone in the locker room likes him.
“We are all very happy to have him here and we hope that he rediscovers his top condition as soon as possible.
“He can provide us with a leap in quality.
“He has played limited minutes so far but when he returns to be at the level of his team-mates, he will play much more.”
Samp travel to Verona looking to halt a three-match winless run.
The Blucerchiati are fifth in the standings, seven points adrift of Napoli, who are third and hold the last Champions League qualifying spot.
“We just have to focus on doing well,” Mihajlovic said. “We are having a good campaign but finishing third is not part of our aim this season.”
Chievo won 1-0 at Parma on Wednesday to record their first win since December 21 and their fifth overall.
Ervin Zukanovic’s goal halted a three-match losing streak for the Flying Donkeys.
The victory lifted Chievo to 17th position, just one place and three points clear of the drop zone.
“Wins give you confidence and we hope we can build on this result,” Chievo coach Rolando Maran said. “We wasted many goalscoring chances against Parma but the important thing is that we brought home a result.”
Maran will have all of his players available.
The visitors are without striker Stefano Okaka, who must serve a one-match ban.