Afonso Alves has been placed in quarantine to keep a stomach bug away from the rest of the Middlesbrough squad.
The Brazil striker missed Boro's FA Cup defeat at Everton on Sunday to ensure the rest of Gareth Southgate's squad did not pick up his illness.
Southgate said: 'Alves went down with the illness on Friday night and we didn't feel he would be well enough to play at Everton. We also wanted to keep him away from the rest of the squad.
'He's had the weekend to try to shake it off and we'll have a look at him, but he should be OK to return to the squad against Portsmouth at the weekend.'
More worrying for Southgate is the injuries Matthew Bates and Justin Hoyte picked up at Goodison. He added: 'Hopefully it's nothing too serious. We need to keep all our players fit for the games which lie ahead of us.'
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