Steven Defour faces a race to be fit in time for the World Cup after the Burnley midfielder had surgery on a knee injury.
Sean Dyche said Defour is "likely" to be out for the rest of the season, with the 29-year-old having been ever-present in the Premier League before suffering the problem.
Defour posted a positive update to social media after going under the knife.
"All went fine," he wrote on Instagram. "Thanks for all your messages. Motivates me to come back as soon as possible."
Despite a nine-game winless run in the Premier League, Dyche's men are seventh in the table following a 1-1 draw at home to runaway leaders Manchester City on Saturday.
Defour was a regular in Belgium's squad through World Cup qualifying, but only featured against Gibraltar in October 2016. Roberto Martinez's side have been drawn with England, Tunisia and Panama at the tournament.