The 31-year-old has spent time out of the sport following career-saving shoulder surgery and returns to action at London's Copper Box Arena for his first fight since January's brutal draw against Badou Jack.
His choice of opponent has been questioned due to Truax's relatively low ranking and DeGale is widely expected to successfully defend his IBF super-middleweight title.
Anything but a win well within the distance would be a surprise, but 'Chunky' is refusing to rise to the bait about his choice of rival and insists his first bout in the UK since 2014 is all about performance.
"I've had a bit of a stick about the opponent to be honest, but he's ranked in the top 15 and this is the perfect fight back," said DeGale.
"He's a fringe world-class opponent, I've just come off surgery and I'll not have boxed for a whole year by the time I fight, so people have to give me a squeeze really.
"If you look at my last four fights I've fought Badou Jack, Rogelio Medina, Lucian Bute and Andre Dirrell, all in North America.
"I deserve someone who's not a world beater. But, listen, these are the dangerous fights, these are the ones where you have to be switched on because he has nothing to lose. It's his chance so I can't take it for granted."