Manchester United are threatening to gain the upper hand over Liverpool in the race for a player described as the 'Colombian Cristiano Ronaldo'.
Luis Diaz has been on the radar of a number of top clubs thanks to his goals for Porto and his breakout international tournament at last summer's Copa America.
The 25-year-old has been described as a "perfect" signing for Liverpool as they aim to address the precarious contract situation affecting their current forward line, but they're not alone in their pursuit of the player.
However, they're not the only team keeping tabs on the former Junior de Barranquilla man, and United's scouts have been hard at work ahead of a potential bid for one of European football's most exciting talents.
Join the debate! Would Luis Diaz be a success in the Premier League? Have your say here.
Read more: Anthony Martial's huge Man Utd bonus clauses and missing £14m speak volumes
Diaz has 14 Primeira Liga goals to his name this season, already his best ever personal return and second only to Benfica's Darwin Nunez in the league standings, and netted twice for his club in the Champions League group stage as Liverpool and Atletico Madrid beat them to a spot in the knockout stages.
He also scored four times at the Copa America, leaving him as joint-top scorer alongside Lionel Messi, as Colombia finished third in the tournament.
Liverpool are believed to consider him a potential longer-term successor to Sadio Mane, who is out of contract in 2023, but United are reported to have stolen a march.
According to O Jogo (via FourFourTwo), Liverpool's failure to act quickly could open the door for their Premier League rivals.
O Jogo also reports that scouts for United were in Portugal over the weekend, along with representatives from Atletico Madrid and Borussia Dortmund, as Porto took on Famalicao in the league.
Scouts from Nimes, Saint-Étienne, Rennes, Real Sociedad and Sassuolo were also at the Dragao, according to the report, though no detail was provided on how many of the scouts were watching Diaz and how many had their eyes on other Porto or Famalicao players.
Diaz played 79 minutes in the game, scoring his team's second goal in a 3-1 victory which saw Porto extend their lead over reigning champions Sporting CP to six points.
United have a healthy-looking forward line at present, but will be in need of longer term reinforcements with a number of their players expected to move on in the coming months.
Anthony Martial is due to complete a loan move to Sevilla until the end of the season, having made clear his desire to leave Old Trafford, while Edinson Cavani could yet leave in the summer when his contract expires.
If Diaz moves to Old Trafford, he would become only the second Colombian to play for United in the history of the Premier League, following Radamel Falcao's year-long loan in the 2014-15 season.
