Barcelona forward Jeffren has been ruled out for up to five weeks after sustaining a hamstring injury in Monday's 1-1 friendly draw against Kuwaiti side Kazma.
Jeffren picked up the knock at the start of the second half and was replaced by Yaya Toure. It is a blow for the 21-year-old who was expected to feature more for the first team when other squad members were away at the African Nations Cup.
Barca boss Pep Guardiola said: "I feel bad for him and for us as we would have needed him during the month of January."
In better news for Guardiola, central defender Gabriel Milito came through 62 minutes as he continues his recovery from knee ligament damage suffered in the Champions League semi-final against Manchester United in April 2008.
"It is nice to play again,'' said the Argentina international. "It is the first game in front of a crowd and edges me closer to regaining the rhythm and fitness levels of my team-mates."