Dragons forward Tyson Frizell backed up against the Titans two days after starring for NSW in Origin III.

Dragons forward Tyson Frizell has been ruled out of the 2017 Downer NRL Auckland Nines, with St George Illawarra staff not wanting to risk the powerhouse back-rower as he continues to work towards full fitness for the start of the Telstra Premiership season.

Initially named captain of the Red V's Nines squad, Dragons head of athletic performance Nathan Pickworth explained it would've been too much too early for Frizell to take part in the frenetic action at Eden Park.

"He's tracking really well, after the Four Nations he did have that back spasm and we've been managing him through rehab and getting him back into training over the past four weeks," Pickworth told dragons.com.au.

"It was just a bit too much of a risk and a little bit too much of a steep incline in training load into the Auckland Nines. 

"We made the educated decision that it would be too much of a risk to play him on the weekend, but he's on track for the Charity Shield and the trial period."

One of the game's great competitors who enjoyed a dream 2016 on the representative front, earning NSW and Australia honours, Frizell was still keen to lead the Red V at the two-day tournament. But with one eye on a long season ahead Pickworth said the 25-year-old eventually accepted the decision.

"He was disappointed, it did take a fair bit of explanation and justifying why we were making that decision to Tyson because he was pretty keen to get over there and captain the team at the Nines," Pickworth said. 

"Once he understood the risks around increasing workloads… he was fully on board with me and my team's decision."

Versatile forward Jacob Host – who recently agreed to a three-year contract extension with the club – has been added to the 19-man squad as Frizell's replacement, while workhorse lock Jack de Belin and Tariq Sims have been named co-captains for the weekend.

Video first featured at dragons.com.au