He is now out of UEFA Champions League quarter-final match versus Bayern Munich.
Pulisic, who scored the Blues’ lone goal during Saturday’s FA Cup final defeat by Arsenal, was later withdrawn from the Wembley showpiece after pulling up with an apparent hamstring issue.
Frank Lampard confirmed immediately after the match that Pulisic – along with Cesar Azpilicueta, who also suffered a hamstring injury during the final – would not feature against Bayern Munich in the Champions League this week, and now the full extent of his injury has been detailed.
The former Borussia Dortmund ace, 21, will be absent for around four to five weeks, talkSPORT sources understand, which means he may not return to training until the week the new Premier League campaign starts on September 12.