Defending champions England Under 20 have named their side to take on Italy in their opening game of the IRB Junior World Championship at the ECO Light Stadium in Auckland on Monday, kick off 06:35 (BST) live on Sky Sports.
Moriarty, a key figure in England's triumphant campaign last summer, starts on the flank with Gloucester team mate Billy Burns named amongst the replacements.
England last faced their Italian rivals in their final game of the U20 Six Nations, winning 52-5, but Head Coach Nick Walshe says that that result will have no bearing on this game.
"We're looking forward to kicking off this campaign, we've been in New Zealand for over a week now - the lads are acclimatised and have trained well. They've taken real ownership and can't wait to get out there.
"We did well against Italy in the Six Nations but that game has gone, we're focused on performing well in this game and kick-starting our JWC. "
Captain Callum Braley added:
"We've enjoyed our first week in Auckland but now it's time to get down to business. We're excited about the next five games - there's pressure on us, but we have to use that to our advantage and perform as well as we can."
England Under 20 starting XV against Italy
15 Aaron Morris (Bedford Blues)
14 George Catchpole (Leicester Tigers)
13 Nick Tompkins (Saracens)
12 Harry Sloan (Harlequins)
11 Nathan Earle (Saracens)
10 Sam Olver (Northampton Saints)
9 Callum Braley (Bristol Rugby, captain)
1 Danny Hobbs-Awoyemi (Northampton Saints)
2 Tom Woolstencroft (Bath Rugby)
3 Paul Hill (Leeds Carnegie)
4 Maro Itoje (Saracens)
5 Tom Ellis (Bath Rugby)
6 Ross Moriarty (Gloucester Rugby)
7 Gus Jones (London Wasps)
8 James Chisholm (Harlequins)
16 Jack Walker (Leeds Carnegie)
17 Alex Lundberg (London Wasps)
18 Biyi Alo (Saracens)
19 Charlie Ewels (Bath Rugby)
20 Joel Conlon (Exeter Cheifs)
21 Henry Taylor (Loughborough University)
22 Billy Burns (Gloucester Rugby)
23 Henry Purdy (Leicester Rugby)
It's the first Gloucester-Bristol derby at Kingsholm in over eight years this Saturday (kick off 4:30pm) and, previewing the game with the local media this week, Defence Coach Jonny Bell stressed that, with both teams in the bottom half of the table, they both need the points.
Speaking to the local media this week, Gloucester front rower John Afoa knows the challenge ahead this week against Bristol, and calls on the Cherry and Whites to make the most of home advantage as a determined squad look to bounce back from a narrow loss to Saracens.
Tom Savage speaks to GRTV and the local media as Gloucester went down by 24-20 at Saracens on Sunday afternoon. The second row was disappointed with the result, despite a strong showing from the hosts.
Speaking immediately after the game, skipper Willi Heinz thought that Gloucester had executed their game plan reasonably well and competed hard against Saracens. However, it wasn't enough but the squad will have plenty to work on this week ahead of the derby match against Bristol.
Gloucester may be coming off their best win of the season, the 38-16 victory over Wasps last weekend, but Director of Rugby David Humphreys admits that Sunday's trip to Saracens is an even tougher test.
After a series of contract announcements last week, hooker Richard Hibbard is the latest Gloucester Rugby player to commit to a new contract at the club and told GRTV how much he enjoys playing in the Cherry and White of Gloucester.
Talk about a game of two halves. Things looked grim on Saturday as Gloucester trailed 0-6 to Bristol at half-time. However, Matt Scott's eighth try of the season got Gloucester off and running, and the visitors fell apart as the Cherry and Whites eased to a 26-18 bonus point Aviva Premiership win.