The Newcastle United forward was taken off after pulling up for the second time with what looked like a groin injury.
Joelinton had tried to play on after pulling up midway through the half.
However, head coach Eddie Howe took him off after the 25-year-old signalled that he couldn’t continue after breaking down.
Joelinton was replaced by Sean Longstaff at Elland Road, where the score was goalless at the break.