Boro striker Rudy Gestede has been sidelined for an “as yet undetermined amount of time” following a “freak injury” to his leg that required surgery.
The 28-year-old suffered an impact injury during training over the weekend, with a strike against his thigh causing a dead leg.
However, Boro boss Garry Monk confirmed that Gestede’s leg started to bleed again after lengthy compression and ice treatment following the incident.
He told reporters: “Rudy’s is a bit of a freak injury really, he had a dead leg but it is quite rare for it to re-bleed after compression.”
“He had a minor operation to relieve the bleeding so we don’t know the extent or timeframe of the injury in terms of the time he will be out. We’re hoping sooner rather than later.”
Summer signing Martin Braithwaite is also expected to miss Boro’s Championship trip to Bolton this Saturday.