Manuel Lanzini is due to arrive in England on Thursday to complete his move to West Ham United, which should free up Stewart Downing to finalise his transfer back to Middlesbrough, HITC Sport understands from sources close to the deal.
West Ham agreed terms with Al Jazira earlier this month to sign the 22-year-old on-loan for the season with a view to a permanent transfer.
Lanzini has an Italian passport, but he has been waiting for the final bits of paperwork to be completed before flying into England to put pen to paper.
He is expected in on Thursday, and Middlesbrough are now expecting that will finally mean West Ham giving Downing the green light to complete his return to The Riverside.
Boro have fought off strong Premier League interest, particularly from rivals Sunderland, to agree terms with West Ham and Downing. HITC Sport understands Boro have agreed to give Downing a five-year deal and will part with a transfer fee of around £7million.
Boro want the deal in place this week, which will then allow them to move on to other targets, with Christian Stuani also expected to sign by the start of next week.
However, another striker remains top of their list of targets and it is understood they are still exploring a deal for Blackburn Rovers frontman Jordan Rhodes.