St George Illawarra Dragons coach Paul McGregor has cut his squad to 20 ahead of the Dragons' Round 13 clash against the Wests Tigers at ANZ Stadium on Saturday afternoon.

McGregor has made a host of changes to the team that was initially named on Tuesday afternoon.

New South Wales Origin duo Josh Dugan and Tyson Frizell will both play, as will skipper Gareth Widdop following his recovery from a knee injury.

Taane Milne, Kalifa Faifai Loa and Tariq Sims return to the interchange as a result of the veteran trio's inclusion, while Kurt Mann has been moved to the centres.

New South Wales Under-20s Origin duo Jai Field and Blake Lawrie are the two players who drop out of the side.

NRL Squad for Round 13 v Wests Tigers

19. Josh Dugan
2. Nene Macdonald
6. Kurt Mann
4. Tim Lafai
1. Jason Nightingale
21. Gareth Widdop (c)
7. Josh McCrone
8. Russell Packer
9. Cameron McInnes
10. Paul Vaughan
20. Tyson Frizell
12. Joel Thompson
13. Jack de Belin
Interchange: 
3. Taane Milne
5. Kalifa Faifai Loa
11. Tariq Sims
14. Jacob Host
15. Leeson Ah Mau
16. Hame Sele
18. Tyrone McCarthy

NYC Squad for Round 13 v Wests Tigers

1. Steven Marsters
2. Matheson Johns
3. Reuben Garrick
4. Zac Lomax
5. Jason Gillard
6. Tristan Sailor
7. Jackson Willis
8. Stuart Mason
9. Reece Robson
10. TJ Uele
11. Jackson Ford
12. Jayden Morgan
13. Joe Lovodua
Interchange:
14. Matt Sheppard
15. Bailey Dickenson
16. Dylan Morris
17. Tom Angel
18. Trent Peoples
20. Max Bailey
21. Cooper Purcell