Dallaglio's return to the England squad for Saturday's championship opener was virtually assured when Worcester's Pat Sanderson suffered a recurrence of his back injury at the weekend.
But the 33-year-old will be restricted to a bench role after captain Martin Corry recovered from bruised ribs and head coach Andy Robinson preferred to start with Joe Worsley at blind-side flanker.
Dallaglio, selected on the bench ahead of Sale's Chris Jones and Gloucester's Jamie Forrester, has only won five of his 73 Test caps as a replacement.
England's starting XV has a familiar look, featuring only three changes - two of them injury-enforced - from the first-choice side that was narrowly beaten 23-19 by New Zealand in November.
Harry Ellis is preferred to Matt Dawson at scrum-half while Matt Stevens has replaced injured prop Phil Vickery and Worsley comes in for Sanderson.
Mike Tindall and Jamie Noon, criticised in some quarters for being too one-dimensional, are once again paired in the centres. Josh Lewsey stays at full-back and Ben Cohen starts on the wing.
Any chance of Robinson shaking up the midfield - perhaps partnering Lewsey with Olly Barkley - was dashed when Barkley dislocated his thumb and Mark Van Gisbergen, Lewsey's potential replacement at full-back, was ruled out with a sprained foot.
Barkley's injury opens the way for Leicester fly-half Andy Goode to provide back-up amongst the replacements for Charlie Hodgson, who needs one point to reach 200 in Test rugby.
Tom Voyce edged out James Simpson-Daniel for a place on the bench, while Simon Shaw provides the second row cover.
Leicester prop Julian White returns to the squad after missing the autumn internationals and Lee Mears provides back-up for hooker Steve Thompson.
England team to play Wales at Twickenham on Saturday:
J Lewsey (Wasps); M Cueto (Sale Sharks), J Noon (Newcastle), M Tindall (Gloucester), B Cohen (Northampton); C Hodgson (Sale Sharks), H Ellis (Leicester); A Sheridan (Sale Sharks), S Thompson (Northampton), M Stevens (Bath), S Borthwick (Bath), D Grewcock (Bath), J Worsley (Wasps), L Moody (Leicester), M Corry (capt, Leicester).
Replacements: L Mears (Bath), J White (Leicester), S Shaw (Wasps), L Dallaglio (Wasps), M Dawson (Wasps), A Goode (Leicester), T Voyce (Wasps).