Hobbs will hit the major milestone and become a centurion for the Blues as Director of Rugby Mark Hammett makes a number of changes to his starting line-up as he looks to manage and utilise his squad over the busy festive and New Year period.
A total of six new faces come into the starting line-up that went on to defeat Scarlets in the first derby encounter of the Christmas period, with hooker Matthew Rees returning to captain the side from the front row.
Former New Zealand international Jarrad Hoeata is declared fit to be named in the second row, where he will partner Lou Reed, while Ellis Jenkins is called in to wear the seven jersey with Sam Warburton ruled out with injury.
Gareth Davies starts the game at fly half, where he will link up with Lewis Jones at half back, and the final change sees a recall for Gavin Evans at inside centre.
Mark Hammett said: "We have to manage the squad and I'm looking at the two Dragons games together; it's important we do. Whoever goes out on the field for us has the responsibility to win these matches and perform.
"We are aiming to secure wins while managing the group to get as much excitement on the park at one time.
"All games are crucial, we always prepare to win and we are looking forward to his derby in front of a big crowd at BT Sport Cardiff Arms Park."
Terrace tickets remain on sale NOW for our Boxing Day fixture with Dragons at BT Sport Cardiff Arms Park. Call the Ticket Office on 02920 302030 or click onwww.cardiffblues.com/tickets to take your seat.
Cardiff Blues: 15 Joaquin Tuculet, 14 Alex Cuthbert, 13 Cory Allen, 12 Gavin Evans, 11 Lucas Amorosino, 10 Gareth Davies, 9 Lewis Jones; 1 Sam Hobbs, 2 Matthew Rees (c), 3 Adam Jones, 4 Jarrad Hoeata, 5 Lou Reed, 6 Josh Turnbull, 7 Ellis Jenkins, 8 Josh Navidi
Replacements: 16 Kristian Dacey, 17 Gethin Jenkins, 18 Taufa'ao Filise, 19 Macauley Cook, 20 Manoa Vosawai, 21 Tavis Knoyle, 22 Gareth Anscombe, 23 Adam Thomas
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