Debut for Thornton against Samoa
The 22-year-old former Wales Under-20 captain is one of seven changes to the starting line-up which helped defeat Tonga in Eden Park last Friday.
In the backs, Aled Davies makes his first international start at scrumhalf, Tyler Morgan lines up at outside centre, and Cory Allen is named on the right wing.
Two of last week's debutants, hooker Ryan Elias and tighthead prop Dillon Lewis, also make their first starts, with openside flank Ellis Jenkins another player to be promoted from the bench.
Two uncapped players are named among the Wales replacements: Cardiff Blues scrumhalf Tomos Williams and Ospreys lock Adam Beard.
Should both make it onto the field at Apia Park on Friday, that would take the new caps on Wales' June tour to 12.
"We've heard throughout the week from local people how much Samoa values Wales as a rugby nation, and there's a weight of history behind that," says McBryde, referencing the groundbreaking matches between the two countries in the late eighties.
"That said, we've been reinforcing the message to the players that there will be nothing friendly about Friday's match.
"Samoa will be smarting from their outing last Friday night at Eden Park against the All Blacks. We've got to be braced for a backlash, a partisan crowd, and look to keep building on the good things we showed in our win against Tonga.
"Training has been hard and the players have been extremely focused, knowing they've got one last chance this season to give a good account of themselves for their country."
Wales: 15 Gareth Anscombe, 14 Cory Allen, 13 Tyler Morgan, 12 Jamie Roberts (captain), 11 Steffan Evans, 10 Sam Davies, 9 Aled Davies, 8 Josh Navidi, 7 Ellis Jenkins, 6 Aaron Shingler, 5 Rory Thornton, 4 Seb Davies, 3 Dillon Lewis, 2 Ryan Elias, 1 Nicky Smith.
Replacements: 16 Scott Baldwin, 17 Wyn Jones, 18 Rhodri Jones, 19 Adam Beard, 20 Thomas Young, 21 Tomos Williams, 22 Owen Williams, 23 Scott Williams.
Date: Friday, June 23
Venue: Apia Park, Apia
Kick-off: 19.30 (07.30 BST; 06.30 GMT)
Referee: Marius van der Westhuizen (South Africa)
Assistant referees: Mike Fraser (New Zealand), Rohan Hoffmann (Australia)
