Northern Ireland defender Jonny Evans will have a scan on a groin injury today.
The 29-year-old centre-half had to be withdrawn during the first half of West Brom's 1-0 defeat at Southampton on Saturday evening.
Northern Ireland boss Michael O'Neill will be sweating on the results of the scan with the first leg of their World Cup play-off against Switzerland just 19 days away.
West Brom manager Tony Pulis said: "Jonny's (injury is his) groin, so we're not sure until we scan it tomorrow.
"Obviously everyone in Northern Ireland will be a little bit concerned about Jonny, and we are a little bit concerned."
Northern Ireland face the Swiss in Belfast on November 9 with the away leg three days later.