Vainikolo will be joined in the three-quarters by former Leicester centre Leon Lloyd and former Munster and Bourgoin scrum-half Mike Prendergast.
But it will be the appearance of Vainikolo that will capture the imagination: "I know Headingley well and I have some good memories of playing there - it will be a good place to start but I am a Gloucester player now and that is where I want to be," he told www.gloucesterrugby.co.uk.
"Pre-season has been good for all of the guys and we are happy. We have trained well and I feel good. We now need to put it in against Leeds this weekend. We are probably still a little bit away from the style of play we are striving for but it is going well.
"I have settled in really well, the boys have been great and it is fantastic being part of the Gloucester family. We have had two games and now I can't wait to get started - it's the real deal now.
"We have to concentrate on what we are doing, we have trained hard for this game and a good start is really important but we know it will be a tough game away from home and we have to be prepared for that.
"I am looking forward to the challenge - it is great being involved."
Vainikolo was confirmed as a Gloucester player in March following a glittering career with the Bulls where he averaged almost a try a game in 150 appearances.
The rest of the team has a settled feel. Prendergast will partner Ryan Lamb in the half-back position and Lloyd will line-up alongside Anthony Allen in the centre. Vainikolo will complete a back three alongside James Simpson-Daniel and full-back Iain Balshaw.
Ryan's forward pack is also experienced and he will welcome back loose-head prop Patrice Collazo, who was blighted with a series of injuries last season, hooker Olivier Azam and tight-head prop Carlos Nieto.
Alex Brown is joined in the second row by Jonathan Pendlebury, while the back row is also settled and includes skipper Peter Buxton at blindside, breakaway Andy Hazell and number seven and Luke Narraway at eight.
"We have to be very careful of this game because Leeds have a history of winning games in the first division, they will be committed to making a statement of what they are about so we are expecting a really difficult contest," Ryan said.
"We are used to very competitive games against Leeds and we will have to be at our best to come out with a win. I am sure the next four to five weeks will throw up some interesting results while the World Cup is on which makes this weekend a massive challenge.
"Leeds will be full of enthusiasm and energy being back in the Premiership and we have to match that."
On the bench, there are places for new hooker Andy Titterrell and prop Christian Califano, lock Dan Tuohy, flanker Alasdair Strokosch, scrum-half Dave Lewis, utility back Willie Walker and full-back Olly Morgan.
Please note that both Adam Balding and James Bailey will travel with the squad.
GLOUCESTER (V Leeds, Sunday, 3pm): Iain Balshaw; James Simpson-Daniel, Leon Lloyd, Anthony Allen, Lesley Vainikolo; Ryan Lamb, Mike Prendergast; Patrice Collazo, Olivier Azam, Carlos Nieto, Jonathan Pendlebury, Alex Brown, Peter Buxton (capt), Andy Hazell, Luke Narraway. Reps: Andy Titterrell, Christian Califano, Dan Tuohy, Alasdair Strokosch, Dave Lewis, Willie Walker, Olly Morgan.
Book your place at Kingsholm for a match of your choice call 0871 871 8781 or visit www.gloucesterrugby.co.uk
Tickets are now available for Worcester on Saturday, September 29th (6.00pm) and Sale Sharks on Saturday, October 13th (3.00pm). Book now, call 0871 871 8781 or visit www.gloucesterrugby.co.uk