The Catalan midfielder has taken a knock to his ankle and might not be fit to link up with Vicente Del Bosque's squad for Wednesday's trip to Guayaquil
The midfielder, who has only just expressed his desire to remain at Camp Nou following reports linking him with a move to Manchester United, put on a scintillating display in Selangor, bagging the opener before playing a part in the Blaugrana's two other goals.
However, Fabregas then limped off with an ankle injury in the 83rd minute, with Martino claiming he would be unable to recover in time for international duty next week.
“He’s received a heavy knock to his ankle," the Argentine coach told reporters. "I don’t know if he’ll be able to play for Spain [in Wednesday's friendly against Ecuador]; he’s not doing great right now."
A notable exclusion from the Barcelona line-up at Shah Alam Stadium had been star striker Lionel Messi, but Martino was quick to allay fears over his compatriot's fitness.
"He was a bit sore and we didn’t want to take any risks. It’s nothing serious but we didn’t want to take the chance," he explained.
With the 26-year-old forward injured, Martino was keen to heap praise on Neymar, who responded well to the responsibility of leading the Liga champions' attack with a goal.
"We are very pleased with how Neymar is performing in the games he has played," the former Paraguay trainer enthused.
"He’s fine, but we didn’t want him to play any more than 45 minutes and, even though he felt good, we didn’t change our plans.
"I’m optimistic, I think we’re in good shape to start the league. The tour has been good from a footballing point of view. We’ve had time to train.
"We’ve got fantastic players, so I’m not going to use a lack of time as an excuse."
The Catalans will begin the defence of their Liga title with a home game against Levante.