Michael Carberry’s replacement in England’s NatWest Twenty20 squad was injured within hours of his call-up.
Carberry, who played his only T20 international against Sri Lanka in May, was replaced by the uncapped Roy, who was hit on the hand while batting for Surrey against New Zealand A and went to hospital for an X-ray.
He at least avoided a fracture but it remained to be seen whether the bruising suffered by the 24-year-old would force him off England duty.
Surrey announced on Twitter: "Result of X-Ray on Jason Roy's right thumb is badly bruised but no fracture."
That injury setback at The Oval came soon after it emerged Bresnan was playing no part in the Roses match at Old Trafford as Yorkshire took no chances with the seamer's pectoral injury.
England named Durban-born batsman Roy and the experienced Bresnan in a 14-man squad to be led by Eoin Morgan for a one-off match which will conclude the international summer at Edgbaston next Sunday.
Roy was handed the call in his breakthrough domestic season, in which he is the country's top NatWest Twenty20 Blast run-scorer with 677 at an average of 48.35 and strike rate of almost 160.
He was joined in the squad on Sunday by three other players not currently involved in the Royal London one-day international series.
They were Bresnan, Ravi Bopara, a surprise omission from the ODI squad, and Nottinghamshire batsman James Taylor.
Morgan was again named captain, as he was for England's Twenty20 against Sri Lanka earlier this summer, in the injury-enforced absence of Stuart Broad - who is set to undergo surgery on his knee this week.
Hampshire T20 captain James Vince was overlooked and Ian Bell, who like Carberry was involved in the defeat against Sri Lanka at The Oval in May, made way for Taylor.
Taylor has not featured for his country since last September's ODI win over Ireland in Dublin but has had a fine season for Nottinghamshire, while former dual Ashes winner Bresnan last played in England's embarrassing ICC World Twenty20 defeat against Holland in Chittagong five months ago.
England squad (v India, NatWest Twenty20 International at Edgbaston on September 7): EJG Morgan (captain), MM Ali, RS Bopara, TT Bresnan, JC Buttler (wkt), ST Finn, HF Gurney, AD Hales, CJ Jordan, JE Root, JJ Roy , JWA Taylor, JC Tredwell, CR Woakes.