The Wales' No.8 has spent the past three seasons with the Melbourne Rebels, whom he has also captained this season.
And having seen some of the Qantas Wallabies attacking talent at first hand, Delve reckons Warren Gatland's men must control affairs up front to stifle the opposition of ball.
"I do think it's going to come down to the Lions' power game against the guile of Genia and Cooper unleashing the Wallaby backs. But I think it'll be a tight one," said Delve.
"That nine-10 combination for the Reds has been on fire this season. Possibly that will swing it the Wallabies way unless we do get a really big advantage up front."
Genia and Cooper's sensational form fired the Reds to the 2011 Super Rugby title and although they were rocked by knee injuries last year, they have returned to their best ahead of the Lions series.
Fly-half Cooper missed out on the cut for Robbie Deans' initial Wallabies squad but six players will be added after the Lions face the Reds on June 8.
One player already assured of their place is scrum-half Genia and Delve is relishing a potential battle with Mike Phillips.
Phillips was on the wrong side of the results as the Wallabies claimed a 3-0 whitewash over Wales last summer and Delve reckons his former teammate must do more to exert his physical dominance.
"I'd say Mike Phillips would be my pick for the Lions scrumhalf and his battle (with Genia) will be huge because both of them can take a game by the scruff of the neck and if it's not going their way, really turn it back towards their team," added Delve.
"They're two different types of players. Mike's almost an extra back-rower with his power game and Will's there pulling the strings with a great running game as well.
"It's certainly where we lost the first test where we didn't keep enough of an eye on Genia up in Brisbane last year. If he has that sort of influence again, it's all game over, really.
"So the halves are definitely going to be a massive point."