Middlesbrough's journey to promotion in 2016 was one of the most exciting periods of the club's recent history.

Aitor Karanka spent three years building a team that ultimately secured a return to the Premier League in the 2015-16 season with almost all of his new signings playing a big role.

For one man, however, it just didn't work out.

Middlesbrough signed Carlos de Pena from Nacional for a fee of £2.6million in September 2015 - a move that was overshadowed by the minor car accident that he was part of on the way to the airport in Argentina as he looked to complete the move.

The left winger never really got going on Teesside and was limited to just 10 appearances in all competitions - four of which came in the cup competitions.

With the Teessiders battling to avoid the drop in the Premier League de Pena was dropped to the under-23 side before being loaned to Spanish side Real Oviedo in January 2017.

At the end of that season the decision was made by Middlesbrough to terminate his contract and allow him to leave.

Since then the winger has surprised supporters by going on to enjoy a remarkable career.

De Pena rejoined former club Nacional for just over a year in January 2018 before securing a big move to Dynamo Kyiv in April 2019.

Since moving to Ukraine the 28-year-old has scored 15 goals and created 13 more in 65 appearances - including 11 in the Champions League where he played a key role in this season's campaign that saw him face Juventus and Barcelona in the group stage.

Now in his prime it'll be interesting to see how the winger fares in Ukraine as he finally starts to show the genuine potential that tempted Middlesbrough into a deal to sign him over four years ago.