The former Tottenham manager has lauded the Chelsea striker on the back of a return to form that has delivered 12 Premier League goals so far this season.
Harry Redknapp admits watching Chelsea striker Diego Costa used to get on his nerves, but says the Spain international has been “fantastic” this season after curbing his temper.
The 28-year-old forward has retained a physical element to his game in 2016-17, but is throwing his weight around to better use.
It used to be that opponents could rile the burly frontman, with a short fuse making him a ticking time bomb.
Last season saw him collect 11 yellow cards and one red, while his debut campaign at Stamford Bridge delivered 12 bookings. So far this term, he’s been cautioned five times.
Costa has also plundered 12 goals, with that return helping Chelsea to nine successive wins and a standing at the top of the Premier League table.
“What he’s done this year, he is concentrating on playing football. He’s still aggressive you can’t take that out of his game,” Redknapp told BT Sport.
“Last year he was more interested in having fights with people than playing football. Every time I saw him he was going out and it was all off-the-ball stuff.
“Really just aggravating – it got on my nerves just watching him play.
“This year he has been fantastic.”
Costa has already matched his Premier League efforts from 2015-16, with 12 goals reached in just 15 appearances.
He will now be looking to break the 20-goal barrier for the second time in his Chelsea career and remain at the top of the charts in the race to land the top-flight Golden Boot.
Arsenal’s Alexis Sanchez is hot on his heels at present, with 11 for the season, while Manchester City’s Sergio Aguero is one effort further back on 10.
Chelsea are next in action on Wednesday evening, when they travel to Wearside to take on struggling Sunderland.
Antonio Conte’s men will then face Crystal Palace, Bournemouth and Stoke during the busy festive period, taking them through to the end of the calendar year.