The Spanish full-back limped off in the second half of Wanderers' game against Blackburn at Ewood Park on Tuesday and left the ground wearing a protective boot.
Coyle said: "There was no new fracture but the pin put in when they did the operation to heal the original fracture took a hit and needs to be replaced so he could be out anything up to six weeks but we're hoping for earlier than that."
He was just two games into his playing return after spending three-and-a-half months on the sidelines with a broken metatarsal suffered in the Carling Cup win over Macclesfield in August.
Coyle added: "The operation will happen today (Friday) and we'll take it from there.
"He came in for the Fulham game the other night and looked assured and destined for a big future.
"I said to him he can handle the level and be comfortable in the environment so when he comes back he'll be able to kick on with his career."
Source: PA
Source: PA