It started with Cristiano Ronaldo and is likely to end with Wout Weghorst -- for now at least. But sources have told ESPN that Manchester United's real objective in their attempt to end a six-year search for a centre-forward is to bridge a gap until the summer when their priority targets will include Victor Osimhen, Benjamin Sesko and, if he opts against signing a new contract at Tottenham Hotspur, Harry Kane.

The £75 million signing of Romelu Lukaku from Everton in 2017 was the only time since Robin van Persie's £24m arrival from Arsenal in 2012 that United have made a significant addition to the front line with a striker in his prime. Radamel Falcao, Zlatan Ibrahimovic, Odion Ighalo, Edinson Cavani and Ronaldo have all arrived at United during the past decade, but all were past their best and signed on short-term deals.

Lukaku was expected to be the solution six years ago, but the Belgium international did not live up to expectations before being offloaded to Inter Milan two years later for around £75m, and United have been patching up their strike force ever since.

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Sources said that the need for United to sign a proven goal scorer in the summer window has been acknowledged within the club and it's regarded as the prime objective. However, United's primary concern right now is to answer manager Erik the Hag's call for immediate reinforcements in the attacking department of his squad following the mutual agreement to terminate Ronaldo's contract in November. And that is where Weghorst neatly fits the bill.

Sources have told ESPN that the Netherlands international, who has spent this season on loan at Besiktas in the Turkish Super Lig from EFL Championship leaders Burnley, could become a United player this week if negotiations involving both clubs and United, as well as the player's representatives, proceed to a swift agreement.

Besiktas don't want to lose the 30-year-old, who has scored nine goals in 18 games for them, but Weghorst has made it clear that he wants to grasp the opportunity of playing for United.

Ten Hag wants an experienced centre-forward, a player to offer a different option to those he already has at Old Trafford. Although the 6-foot-6 Weghorst struggled to make an impact in the Premier League with Burnley last season, where he scored just two goals in 20 appearances, his performances at the World Cup with Netherlands -- he scored twice late on in the quarterfinal against Argentina before defeat in a penalty shootout -- underlined his ability to trouble the best defences.

But Weghorst is regarded as a short-term fix and the hope within United is that, after so many stop-gap signings in the attacking department, he will be the final temporary solution. United's search for the right signing this month has been carried out within some strict guardrails, however.

Sources told ESPN that the majority of options available are either "castoffs who don't play, strikers who have been injured, or those who just aren't good enough." Another issue is that many players will only discuss a move if it involves a contract no shorter than 18 months, which would ensure a deal at Old Trafford until June 2024, and sources said that United have ruled that out because they want a clean slate at the end of the season. That means no obligation to pay a striker who won't play for another 12 months.

Sources said that United didn't make a transfer bid to sign PSV Eindhoven's Cody Gakpo, who completed a £37m switch to Liverpool last month, despite Ten Hag earmarking the player as a possible signing. And while a move for AC Milan's Olivier Giroud was considered, with the 36-year-old's contract at San Siro due to expire in six months, sources added that the complications of the Italian tax system would have meant the France international facing a significant tax bill if he were to depart before the summer, which ruled out the prospect of a short-term deal at Old Trafford.

So Weghorst works for United in terms of the criteria the club has laid out. If United can negotiate a way for the player to cut short his loan at Besiktas, they would have a proven striker who would return to Burnley once this season is finished.

By that stage, United would hope to have secured qualification for next season's Champions League. Ten Hag has made it clear that a new striker is needed to help secure a top-four finish and such an achievement would boost their chances of signing their favoured attacking option.

Napoli forward Osimhen is high on that list. The 24-year-old Nigeria international has scored 11 goals in 16 games for Napoli this season and is regarded as fitting United's profile in terms of age and ability, although sources have said that Paris Saint-Germain are likely to be interested in signing him too.

Sesko, the 19-year-old FC Salzburg forward, is another option, albeit at the younger end of the scale. United considered a move for the Slovenia international last summer before RB Leipzig -- Salzburg's sister club within the Red Bull group -- agreed a £20m deal to sign him at the end of this season. Despite that agreement, sources said that Sesko might still be available if a club are prepared to make a higher offer to buy Leipzig out of the deal.

And then there is Kane, the England captain, who will enter the final 12 months of his Tottenham contract this summer. The 29-year-old striker almost left Spurs in 2021 before Manchester City abandoned their attempts to sign him. But with the prospect of Kane leaving as a free agent in 2024, both player and club face a decisive summer, and sources said that United are aware that they may be the most attractive option for Kane should he choose to seek a move at the end of the season. With City signing Haaland for £51m last summer and Liverpool adding Darwin Nunez and Gakpo in recent months, United are best placed within the Premier League to land Kane, who is now just 62 goals behind Alan Shearer in the all-time scoring charts in the league.

Whoever United target in the summer, they need to be in the Champions League to have a realistic hope of signing them. And that's why they are moving to sign Weghorst. He is a means to an end, but right now, he is the best available option.