Torres will have a scan on the injury on Wednesday, the club said but Mourinho was confident the problem was not serious.
"Our doctor is confident it is not a big injury like (Marco) Van Ginkel's (out for six months), but we will have to wait for the scans,' Mourinho said on the Chelsea website (www.chelseafc.com).
"Torres knows that he doesn't play against Norwich (due to suspension). Then he knows he doesn't go with the national team, so he has time before the next game he can play, against Cardiff (on October 19). Let's see the scan.
"It is a pity for the guy because he is in a very good moment physically and he played fantastic against Tottenham (last weekend), and he played today because he deserved to start. It is a pity but that is football," the Portuguese added.
Torres, who was sent off against Tottenham Hotspur, left the pitch with a knee injury after 11 minutes of Tuesday's 4-0 win in Romania.
Spain host Belarus on October 11 and Georgia four days later in World Cup qualifiers. The world champions are unbeaten at the top of Group I with 14 points from six matches.
Image: Fernando Torres
Photograph: Clive Rose/Getty Images
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