Gomez was "happy" to see the 26-year-old in action in the recent friendly and will be delighted by Southampton's accomodating action.
"With only two games left we decidied the best course of action would be for him to go home," Southampton chairman Rupert Lowe confirmed on his club's website.
"He can continue with his rehabilitation and concentrate on the World Cup.
"We have a good relationship with the Ecuadorean FA and they appreciate what we have done."
Delgado has scored 29 goals in 43 internationals but has only played 143 minutes for the Saints since his £3.5m move.
"Delgado is happy with the decision and has pledged to come back and show our fans what he can do," Lowe added.
"Everyone is comfortable with this decision. We wish him well in the tournament and hope he scores a lot of goals," he concluded.