Todd returns in midfield after missing last weekend's trip to Northampton through flu, whilst the club's front row options are boosted after Roncero's return from Argentina World Cup duties.
Openside flanker Andy Hazell misses out after receiving a club suspension following his involvement in last weekend's fracas at Franklin's Gardens.
Gloucester captain Jake Boer moves to the openside and James Forrester comes in to wear the No.8 shirt. Peter Buxton moves to the blindside.
The Gloucester replacements bench is without Scotland international Steve Brotherstone, who is absent with a knee injury, the hooker is replaced by Academy product Chris Collins.
Welsh U21 and Sevens international James Merrimen is also named as a replacement back row forward.
Gloucester: 15 Jon Goodridge, 14 Marcel Garvey, 13 Robert Todd, 12 Henry Paul, 11 James Simpson-Daniel, 10 Duncan McRae, 9 Alex Page, 8 James Forrester, 7 Jake Boer (captain), 6 Peter Buxton, 5 Alex Brown, 4 Adam Eustace, 3 Andy Deacon, 2 Chris Fortey, 1 Rodrigo Roncero.Replacements: 16 Chris Collins, 17 Nick Wood, 18 Adrian Olver, 19 Mark Cornwell, 20 James Merrimen, 21 Simon Amor, 22 Josh Frape.
Kick-off: 15.00 GMT