The 2018 World Cup is well underway and there are a number of nations that have impressed and players that have already made a big impression for their country in their opening group game, and surely some of them will have caught the eye of Southampton manager Mark Hughes.

The Welshman will be determined to strengthen his squad this summer after they came within a whisker of suffering relegation to the Championship last season, and he has already lost out to Leicester City after agreeing a club-record fee for Norwich City for attacking midfielder James Maddison.

The former Stoke City chief, who only needs to make two signings this summer if he keeps his squad together, certainly will look to bounce back from that blow and add more quality additions to his side in order to ensure they don't find themselves in a similar predicament again next term, with defensive and attacking additions surely a priority given the south coast outfit's poor record at both ends of the pitch during the 2017/18 campaign.

He will already have his targets in mind, but he may well have been convinced by the displays of a number of individuals in Russia, too.

Here are three World Cup stars that Hughes has surely added to his summer transfer wishlist…

It was clear to see last season that Southampton were missing a real experienced leader at the heart of the back four following the departures of two captains in Jose Fonte and Virgil van Dijk over the course of the last 18 months, and it is something that Hughes needs to put right this summer.

The likes of Wesley Hoedt and Jack Stephens struggled without a senior player alongside them, and the south coast outfit may have their ideal answer in the form of Schar, who helped Switzerland pick up an impressive 1-1 draw against pre-tournament favourites Brazil in their opening group game on Sunday.

The 26-year-old reportedly has a release clause of just €4m (£3.5m) following Deportivo La Coruna's relegation from La Liga, and he could be a bargain buy.

Another experienced centre-back who could fill the void left by the likes of Fonte and Van Dijk is Mexico international Moreno, who was brilliant for his country as they kept a clean sheet and picked up a 1-0 win against the World Cup holders Germany on Sunday.

The 30-year-old Real Sociedad defender has plenty of experience in European football and almost 100 caps for his country, and he would prove to be a really useful addition to the Saints backline both in terms of being a leader, as well as his defensive qualities.

Southampton are in desperate need of some attacking reinforcements this summer after scoring just 37 goals in their 38 Premier League matches during the 2017/18 campaign, and they probably need some options out wide with the likes of Sofiane Boufal and Nathan Redmond often failing to deliver.

One option for them could be Peru winger Carrillo, who was brilliant in his nation's 1-0 defeat against Denmark on Saturday.

Despite a disappointing season-long loan spell with Watford last term in which he scored two goals and provided two assists in 30 appearances in all competitions for the Hornets, the speed, skill and strength he showed against the Danes suggest he could make a big impact for Saints in the Premier League.

Do you agree, Saints fans? Let us know below.