The pair are joining the Super League side from Manly for the Middle 8s.
Watson is hopeful that playmaker Mateo can give the Red Devils a new dimension.
“He’s got so much skill with the ball in hand as well,” he said.
“He’s played at the highest level in the UK, you don’t play that at level if you can’t defend. The skill level he can add on the back of that to our attack game, he can give us another dimension.”
Watson believes Burgess can act as another leader for his squad.
“Luke’s a player who’s played at the top level, he’s won grand finals in the NRL so him coming across here will give us another solid middle,” he said.
“He can give us some real good go-forward. Hopefully as well he can be real a leader for us as well.
That’s something we have missed in the group is that little bit more of another experienced leader and hopefully he can bring that in with him.”
Salford winger Justin Carney is expected to be fit to return from injury for the club’s first Super 8s game in two weeks time.