The 25-year old midfielder - who has been capped eight times by his country - currently plays for Colombian Categoria Primera A champions Atletico Nacional, although, following strong displays in the World Cup, a move to a top European league has been touted.
He frequently plays as a defensive midfielder, and is praised for his combative spirit and his ability to quickly turn over play with hard tackles and precise passing. He featured in four of Colombia's five games at the Brazil-based tournament, where he recorded the highest pass completion rate for any Los Cafeteros player - 91.7%.
His form notified the scouts of a host of clubs, including Olympiakos and Roma, and, according to Voci Di Sport, Serie A club Udinese Calcio have won the race for his signature. The Udine-based club agreed a deal with Atletico for the transfer of the player, with a fee of around €4 million believed to have been exchanged.
However, it is unlikely that Mejia will turn out at Stadio Friuli this season, with their designated slots for extra-EU players all filled.
This squad restriction opens the door for a temporary move away from Udine, and the same report suggests that both Championship club Watford, and recently promoted Serie A side Cesena, are interested in taking him on loan.
Due to the close relationship between Udinese and Watford, with both clubs owned by the same family, a move to Hertfordshire seems most likely, and a player of Mejia's quality would certainly aid the Hornets in their search for promotion.
He would be the second signing to arrive this summer following appearances at the World Cup - with Ecuadorian Juan Carlos Paredes set to join up with the squad in the coming days - and to be filling the first-team squad with such talents can only suggest a bright future for those involved with the Vicarage Road outfit.