Experienced second-row Pitts and full-back Hampshire were not ready for Saturday’s Super League opener against Leeds Rhinos which Trinity lost 28-22.
However, they are named to face Wigan at St Helens with Chester hoping they will have an instant impact.
“It’s a real big boost,” he said.
“We’ve got our vice-captain Jay Pitts back in and Rocky Hampshire.
“Pittsy brings leadership more than anything else. We look a good defensive side when he's out there.
"It’s important we try and keep that right edge together; last year Reece Lyne played with three or four different guys inside him and outside him.
“Pittsy brings a calmness and he’s a really good talker on the field.
“Rocky will play as well and what he brings is he works hard in yardage.
“He’s a half-back playing at full back and just a a smart footballer.
“To have Rocky back in and Pittsy is a real big boost.
“We talk about competition for places and we have plenty.
“There’s some guys that played last week that are probably on notice as well.
“Those guys know that they need to perform a little bit better than they did last week.”
Hampshire replaces Alex Walker who has been struggling with a back issue.
Hooker Kyle Wood has had a setback with his calf injury and is set for another scan.
He could be missing for another three weeks but prop Eddie Battye is ahead of schedule and could return next week.
Wigan - led by Chester’s former Warriors team-mate Adrian Lam - edged past promoted Leigh Centurions in their first game of the season but saw NRL signing Jai Field injured on debut and subsequently ruled out for five months.
However, Great Britain half-back and former Man of Steel Jasckson Hastings returns for them.
Chester said: “It’s not the Wigan of old is it but, having said that, you look at the pack, they have some big blokes in there.
“They are a big, physical team and they’ll want to bash us early doors.
“We just have to match their physicality and be aggressive and just be a little bit smarter in how we get out of yardage.
“I’m pretty sure I know what Lammy is going to do in terms of the kicking game and where he wants to put us and too many times last week we got held up and dragged back. We’ve worked on that.”