Erik ten Hag has used the Qatar World Cup to identify a number of January transfer targets following Cristiano Ronaldo's exit from the club earlier this month, according to reports. 

United will look at a shortlist of options which, according to ESPN, includes 2022 World Cup goalscorers Cody Gakpo and Rafael Leao, with the former having been of interest last summer. 

Ronaldo left the club by mutual consent after an outlandish interview with Piers Morgan resulted in several allegations and accusations being levelled at the club. 

Erik ten Hag is thought to be keen for Manchester United to reinforce their squad up front

In the 37-year-old's absence, Ten Hag can still call upon the services of both Marcus Rashford and Anthony Martial but he will be under pressure from the club's sizeable fanbase to bring in a replacement for Ronaldo. 

Both Gakpo and Leao have found themselves on the watchlists of Europe's top clubs after breakout years with PSV and AC Milan respectively.

Having spent in the region of £220million in the last transfer window on the likes of Casemiro, Antony and Lisandro Martinez, United were not thought to be keen on making significant changes this January. 

However Ronaldo's acrimonious exit has left the club somewhat short-staffed up front, although his departure will save the club around £16m in wages. 

Martial has a long history of injury issues, and though Rashford has shown that he can lead the line for United at times this term, he will need support if he is to lead the line, having only scored 20 goals or more in a single campaign twice. 

And with a hectic schedule anticipated after the mid-season break for the Qatar World Cup, Ten Hag is still competing on four fronts and will want to bring in reinforcements as soon as possible. 

Gakpo caught his eye last summer, although the PSV forward reportedly snubbed the move as Ten Hag turned his attentions to Ajax's Antony. 

Gakpo's electric form this term has bled into the World Cup, with two goals in his first two games in Qatar, having managed 17 goals and 18 assists in all competitions, attracting interest from both Leeds and Southampton. 

Leao has also been the subject of interest, with Chelsea thought to be admirers of the Portuguese youngster, who has also been on the scoresheet for his country in Qatar. 

The winger came on in the second-half of their opener with Ghana and helped solidify a win after scoring just minutes later with a well-taken finish.  

The 23-year-old has grown in importance at AC Milan, after helping them end their title drought with 14 goals in 42 appearances last term from the wing. 

However, neither player will come cheaply, with PSV valuing their star at at least £43m (€50m), and Leao already being reported at costing Chelsea more than £100m amid their pursuit of the forward.