Sione Tuipulotu makes his first Glasgow Warriors appearance since January in as Smith's men chase a place in the quarter-finals.
The 27-year-old is one of 11 Scotland internationals named in the starting XV for tomorrow's trip to London, as the Warriors go in search of only a third-ever quarter-final in Europe's premier club rugby competition.
Johnny Matthews comes into the front-row in the only alteration to the trio that started last weekend's 45-3 win over the Scarlets, as Nathan McBeth and Zander Fagerson pack down either side of the hooker.
The second-row partnership is unchanged, meaning Scott Cummings - a try-scorer in Llanelli last weekend - partners Max Williamson in the engine room.
An all-Scotland combination sees Matt Fagerson and Jack Dempsey restored to the starting XV after being rested for last weekend's visit to Parc y Scarlets, Rory Darge completing the back-row triumvirate.
Tom Jordan shifts to the fly-half jersey to accommodate the return of Tuipulotu in the midfield, with George Horne partnering the former Ayrshire Bull in the half-backs.
Stafford McDowall moves to outside centre as he partners the returning Tuipulotu, the pair having most recently started in the midfield together in January's clash with Exeter Chiefs at Sandy Park.
Club captain Kyle Steyn is another to return to the lineup after being rested for last weekend's win over the Scarlets, as Kyle Rowe - fresh from his hat-trick last time out - and Josh McKay round out the starting XV.
Gregor Hiddleston rotates to the replacements bench after scoring his first try for Glasgow Warriors last weekend, the hooker joining Oli Kebble and Lucio Sordoni as the front-row cover tomorrow night.
Sintu Manjezi wears the number 19 jersey, whilst Ally Miller - in the week in which he extended his contract with the club - and Henco Venter complete a six-two split of forwards and backs.
The back-line is covered by Jamie Dobie and Duncan Weir, the latter having started both of Glasgow's last two matches in the BKT United Rugby Championship.
Speaking following selection, Head Coach Smith told glasgowwarriors.org: "Training this week has been competitive, with everyone looking to put their hand up for selection.
"We're pleased to welcome Sione back into the starting lineup, and his return is testament to the hard work and dedication of both Sione and our medical and S&C teams.
"We also look forward to seeing and hearing our travelling supporters in the stands tomorrow night, as they continue to join us on our European journey."
15 Josh McKay
14 Kyle Steyn (Captain)
13 Stafford McDowall
12 Sione Tuipulotu
11 Kyle Rowe
10 Tom Jordan
9 George Horne
1 Nathan McBeth
2 Johnny Matthews
3 Zander Fagerson
4 Max Williamson
5 Scott Cummings
6 Matt Fagerson
7 Rory Darge
8 Jack Dempsey
Substitutes
16 Gregor Hiddleston
17 Oli Kebble
18 Lucio Sordoni
19 Sintu Manjezi
20 Ally Miller
21 Henco Venter
22 Jamie Dobie
23 Duncan Weir
(146)
Unavailable for selection: Jamie Bhatti (foot), Fraser Brown (knee), Sebastian Cancelliere (knee), Richie Gray (bicep), Huw Jones (hand), Jack Mann (ankle), JP du Preez (knee), Ollie Smith (knee), George Turner (foot), Sione Vailanu (knee).