"He's really nervous and we want to give him time to grasp all the information before we put him out there," Tietjens said. "He could be in Wellington, and will more than likely be in Wellington. Remember, we are playing very experienced teams in the world series. We want to make sure he's really ready to go."
He should be able to adjust, given he's gone from rugby league to rugby union and back again twice. He's also dabbled in professional boxing in an extraordinary career.
"I have confidence that I will be able to pick it up eventually," Williams said.
"I know I have a lot to learn and know where I'm at but I have faith in my ability and what I can bring to the table."
It will be Tietjens' job to juggle the available resources. There aren't as many All Blacks as first thought when sevens was added to the Olympic programme, with most prioritising the All Blacks jersey over the prospect of Olympic gold, but the likes of the Ioane brother, Akira and Reiko, as well as Ardie Savea are also in the mix.
The New Zealand sevens side have endured a difficult start to their world series campaign, and are in the unfamiliar position of seventh after two of the 10 rounds after being hit by multiple injuries, but Tietjens has plenty of firepower to call on. He said he will put out different combinations in the next six rounds before settling on close to his Olympic squad for the Paris and London legs in May.
"Coming into this environment is a little overwhelming," Williams said. "I watched a lot of sevens last year and just seeing some of the magical things they can do... I'm a little bit starstruck."
It doesn't mean they get All Black treatment. Williams might be used to five-star treatment but had to cope with a bunk bed like the rest of the squad in sevens camp.
"No bullshit," Williams said of the environment. "It's just about getting the job done."
They should have a better chance of doing that with Williams on deck.