Coleman was substituted in the closing stages of Monday's 1-1 draw at The Hawthorns, with manager Roberto Martinez subsequently confirming the 25-year-old had felt pain in his hamstring.
A further update from Everton's official website on Wednesday revealed the nature of Coleman's injury, but did not put a timescale on the Republic of Ireland international's likely absence.
"Seamus Coleman has suffered a 'minor soft tissue injury'," read the statement.
"The defender was forced off during Everton’s 1-1 draw with West Bromwich Albion on Monday night.
"He has been closely monitored by Blues medical staff since then and has already begun his recovery."
Coleman has enjoyed a fine season under Martinez to date, scoring five league goals to more than double his previous tally for Everton.
