England defender Ashley Cole is an injury doubt ahead of the World Cup qualifying double-header against Montenegro and Poland after being substituted with a long-standing rib injury in Chelsea's win over Norwich City.
Cole was replaced by Eden Hazard after 75 minutes at Carrow Road and will undergo a scan on a rib problem before joining up with the England squad at St George's Park on Monday.
The 32 year old, one of three players in Roy Hodgson's squad to have won over 100 international caps, is among the most experience members of an England squad which requires two wins against Montenegro and Poland to reach the 2014 World Cup in Brazil and his absence will be a significant blow.
"He was feeling it hard in the ribs but I didn't change him because of that," Chelsea boss Jose Mourinho said. "I changed him [to have] an option in the game, a tactical decision, but I realise the situation before was difficult for his condition.
"It is my concern because I want England to do well and my players to play for their national team. But we need to assess the injury.
"Hopefully he will be fine but he'll go for a scan on his ribs when we arrive home, and I hope he is OK. I want England to do well, and I will be there at Wembley on Friday to push, as I would love England to go to the World Cup."
Cole has started every Premier League and Champions League game for Chelsea this season; a rare mainstay in the opening weeks of Mourinho's second spell at Stamford Bridge, while he has begun England's last four World Cup qualifiers.
With Cole's involvement hanging in the balance, Leighton Baines, the Everton left-back, is the natural replacement in defence while Ryan Bertrand or Luke Shaw, who is included in Gareth Southgate's England Under-21, are likely to be called-up as replacements.
Injury to Cole ends a weekend where Hodgson was sweating over a series of injury concerns. Both Wayne Rooney and Daniel Sturridge suffered respective foot and hamstring problems during Manchester United and Liverpool's wins over Sunderland and Crystal Palace respectively but are both expected to be available.