Ashley Fletcher hasn't started for Middlesbrough in the Championship all season, and struggled at Sunderland last season too.
Middlesbrough travel to Hull City this weekend in an all-important fixture.
Middlesbrough sit second in the Championship, having lost just one game all season.
Middlesbrough have now kept seven clean sheets this season.
Middlesbrough travel to Deepdale to face Preston North End in the Carabao Cup on Tuesday evening.
Adama Traore joined Wolverhampton Wanderers from Middlesbrough in the summer transfer window.
George Saville joined Middlesbrough from Millwall in the summer.
Middlesbrough face Swansea City in the Championship on Saturday.
Middlesbrough beat Bolton Wanderers 2-0 on Wednesday evening.
Middlesbrough's Adam Clayton has impressed in the Championship so far this season.
Middlesbrough hope to name Tony Pulis as their new manager by the end of the week and, ideally, as early as Boxing Day, when Bolton Wanderers visit the Riverside.
Carvalhal's fate as Sheffield Wednesday manager could be decided after Saturday's visit of Middlesbrough.
Swansea sacked Paul Clement after a run of terrible form, now they're allegedly after Slaven Bilic. Here's why that's a terrible idea: