|Euro 2020: Northern Ireland v Estonia|
|Venue: National Stadium at Windsor Park, Belfast Date: Thursday, 21 April Kick-off: 19:45 GMT|
|Coverage: Live on Radio Ulster, text & audio commentary on BBC Sport website & BBC Sport App, highlights on BBC2 NI 19:00 GMT on Friday, 22 March|
Sunderland striker Will Grigg has been ruled out of Northern Ireland's Euro 2020 qualifiers against Estonia and Belarus with an ankle injury.
The 27-year-old has returned to his club and will miss the matches at Windsor Park on Thursday and Sunday.
Defender Gareth McAuley and midfielder Corry Evans are doubts for Thursday's Estonia game, having joined the squad with ongoing hamstring problems.
Oxford United's Gavin Whyte is also a slight concern with a thigh injury.
"Will's ankle is an ongoing problem that he's had for some time," said Northern Ireland manager Michael O'Neill.
"He wasn't going to be in contention for Thursday night and it was unrealistic to expect him to be ready for Sunday."
On McAuley and Evans, O'Neill added: "We'll see how they are in the morning. They've made good progress this week but we knew this game would come too soon for them, probably."
Former Wigan Athletic forward Grigg, who has scored twice in 13 appearances for Northern Ireland, had been recalled to the squad after missing the last three internationals due to injury.
Kyle Lafferty, Liam Boyce, Josh Magennis, Conor Washington and the inexperienced Paul Smyth are the remaining strikers in O'Neill's squad for Northern Ireland's opening two Euro 2020 qualifiers.