"Ben’s been fantastic. I can’t speak highly enough of him," Deledio said from Punt Road on Tuesday.
"I never realised how much of a team player Ben was until you witness it first-hand.
"I haven’t seen anyone drive as much to help out another teammate as he has, and to see his work rate on game day is phenomenal."
Deledio also said Cousins was a terrific leader who he “absolutely” wanted to be a Tiger again in 2010.
Cousins has always been one of the hardest trainers in the AFL – regularly throwing up on Subiaco Oval when at West Coast – but Deledio said that now the four-time Eagles club champion and six time All-Australian was 31, he was more focused on looking after his body and getting himself right for matches.
"He grows another leg, as he would put it," Deledio said.
"He gets himself right for game day – he trains really hard and works his behind off in the gym, but it’s more so game day that I’ve noticed."
Cousins was overlooked by all clubs in the 2008 NAB AFL Draft and again by five clubs in the 2009 NAB AFL Pre-season Draft. But the Tigers took a punt with pick No.6 and Cousins arrived in Melbourne to an enormous fan-fare.
The media conference after the Tigers took the Brownlow Medallist was the biggest of the year by a fair margin.
But the season started poorly for Cousins when he tore his hamstring in the season opener against Carlton, and many pundits questioned the wisdom of drafting a 30-year-old to a club that already had the highest number of players in the competition over that age.
But since his return in round seven, Cousins has slowly made his way back towards top form, with his 35-possession performance last weekend against Carlton his best for the year.
He earned eight of a possible 10 votes from coaches Brett Ratten and Jade Rawlings in the AFLCA Crown Champion Player of the year award.
The Tigers face North Melbourne on Sunday in their round 16 match at the MCG.
