That does not make them any less dangerous, mind.
Rankin, who will look to help orchestrate a win for his side on Thursday night that would see them replace Hull in fourth, played alongside the effervescent and gifted Kelly at Gold Coast Titans in 2013.
Two years later, he was also a team-mate of the prolific Sneyd at the Black and Whites before heading home to Australia to join Wests Tigers.
Clearly, the battle of the playmakers – Castleford also boast Super League’s ‘Young Player of the Year’ Jake Trueman – should be fascinating at Wheldon Road.
“Sneyd’s probably their threat when it comes to the last tackle options,” said Rankin about the two-time Lance Todd Trophy winner, who could surpass 1,000 points for Hull.
“Alby’s a strong runner of the ball, creative, has scored a lot of tries throughout his career and recently for them as well.
“They are players who can put you to the sword – Hull have players like that. Jake Connor comes up with a lot of stuff individually and that’s something we’ll have to be wary of come Thursday night.
“We have to be on it defensively if we’re going to shut down a Hull team that’s been playing pretty decent footy over the last month or two.
“It’s a massive game for us; they are close to us on the table so to get the two points off them would be a massive step towards us securing a top-five place.”
Castleford are looking to make it back-to-back victories after a priceless ‘Golden Point’ extra-time 27-26 success over Huddersfield Giants on Friday.
That game saw Rankin – who is on a season-long loan from Giants – make his first start since a two-month injury lay-off.
“It’s an interesting time playing two of my old teams in the space of two weeks,” he said, having scored 23 tries in 47 games for Hull during 2014 and 2015.
“Huddersfield was a good opportunity for us to right some wrongs that we had against St Helens at Magic Weekend.
“To do that in ‘Golden Point’ was a thrilling way to end a decent week’s training and it was really good to be back starting. It was frustrating being out seven, eight weeks, not being able to help the boys as much as I’d like to.
“But slowly over the last month I’ve played progressively more minutes until finally filling that role of playing a full 80 as a half.
“It’s something I really enjoyed; I was able to have a bit more of a say on how the game played out.”
That said, he conceded his badly scuffed drop-goal attempt was not one of his “brightest moments” before Peter Mata’utia did finally settle things but it will not deter him from lining up again.
Rankin – who hopes to have his loan extended at Castleford – is only 27 but has been around for more than a decade given he is one of the youngest Australian first-grade debutants, making his bow with Titans aged just 16.
On his time at Hull, he added: “I loved it there. It was an opportunity for me to come over from Australia and they welcomed me with open arms.
“It was a club I really enjoyed playing at. I bought into the culture, what the team and club was about, and I look back on it with fond memories.”
Head coach Lee Radford remains and Rankin conceded: “He is tough. But he’s fair as well.
“He just wants the best for his players and the club itself; he’s a Hull lad that played there and he’s done some special things for the club over the last few years.
“I hear a lot saying he should be sacked and they need someone new. But he’s got two Challenge Cup wins, is constantly taking them to top five places and he’s done a pretty good job with the playing group that he’s got. He doesn’t need that criticism.”