Leicester Tigers centre Tuilagi has made three appearances on the tour so far but missed the opening two Tests.
He is named among the replacements on Saturday alongside club colleagues Tom Youngs and Dan Cole, with Geoff Parling retaining his place in the second row. There is no place for Ben Youngs and Tom Croft who were both involved in the opening two Tests against the Wallabies.
Alun Wyn Jones captains the team in Sydney following injury to Sam Warburton in a team showing six changes to the one that started last Saturday’s second Test in Melbourne.
Sean O’Brien takes Warburton’[s place in the back row, Jamie Roberts replaces Brian O’Driscoll in the centre and scrum-half Mike Philips has recovered from a knee injury to start instead of Ben Youngs. Alex Corbisiero returns from injury to replace Mako Vunipola, Richard Hibbard makes his first Test starting appearance at hooker, while Toby Faletau makes his Test debut at No.8 in place of Jamie Heaslip.
Lions coach Warren Gatland said: “It all comes down to Saturday. Winner takes all. We know we can leave nothing in the tank and that only a complete performance will get us across the line.
“Picking this team was not easy and ultimately with several players available after recovering from injury the head over-ruled the heart in many selection decisions.
“It has been a challenging tour and we have had our fair share of injuries but we always knew that would be the case. Brian O’Driscoll is a great player and has had a wonderful career but for the final Test in Sydney we just felt Jamie Roberts' presence offered us something more. Mike Phillips and Alex Corbisiero were first Test selections and would probably have played in the 2nd Test if not for injury. Richard Hibbard, Toby Faletau and Sean O’Brien have also earned their starting places.”
Tour manager Andy Irvine said: "It is amazing that the last three series between the Lions and the Wallabies have gone down to the last Test. In 1989 the Lions triumphed, in 2001 it was the Wallabies who won the series and now in 2013 we go to ANZ Stadium in Sydney with the series and the Tom Richards Trophy up for grabs.
“There is nothing between these two teams, with the last two Tests being decided in the dying moments. The Test is a sell out and the whole rugby world is looking forward to the match with great anticipation.”
British & Irish Lions (v Australia, July 6, Sydney)
15 Leigh Halfpenny (Cardiff Blues/Wales)
14 Tommy Bowe (Ulster/Ireland)
13 Jonathan Davies (Scarlets/Wales)
12 Jamie Roberts (Cardiff Blues/Wales)
11 George North (Scarlets/Wales)
10 Jonathan Sexton (Leinster/Ireland)
9 Mike Phillips (Bayonne/Wales)
1 Alex Corbisiero (London Irish/England)
2 Richard Hibbard (Ospreys/Wales)
3 Adam Jones (Ospreys/Wales)
4 Alun Wyn Jones (Ospreys/Wales)(c)
5 Geoff Parling (Leicester Tigers/England)
6 Dan Lydiate (Dragons/Wales)
7 Sean O’Brien (Leinster/Ireland)
8 Tangaki Taulupe Faletau (Dragons/Wales)
16 Tom Youngs (Leicester Tigers/England)
17 Makovina Vunipola (Saracens/England)
18 Dan Cole (Leicester Tigers/England)
19 Richie Gray (Scotland)
20 Justin Tipuric (Ospreys/Wales)
21 Conor Murray (Munster/Ireland)
22 Owen Farrell (Saracens/England)
23 Manusamoa Tuilagi (Leicester Tigers/England)
15 Kurtley Beale (Melbourne Rebels)
14 Israel Folau (NSW Waratahs)
13 Adam Ashley-Cooper (NSW Waratahs)
12 Christian Leali’ifano (Brumbies)
11 Joe Tomane (Brumbies)
10 James O’Connor (Melbourne Rebels)
9 Will Genia (Queensland Reds)
1 Benn Robinson (NSW Waratahs)
2 Stephen Moore (Brumbies)
3 Ben Alexander (Brumbies)
4 Kane Douglas (NSW Waratahs)
5 James Horwill (Queensland Reds)(c)
6 Ben Mowen (Brumbies)
7 George Smith (Brumbies)
8 Wycliff Palu (NSW Waratahs)
16 Saia Fainga’a (Queensland Reds)
17 James Slipper (Queensland Reds)
18 Sekope Kepu (NSW Waratahs)
19 Rob Simmons (Queensland Reds)
20 Ben McCalman (Western Force)
21 Michael Hooper (NSW Waratahs)
22 Nick Phipps (Melbourne Rebels)
23 Jesse Mogg (Brumbies)