Rating the 'Big Four' Premier League arrivals

With the World Cup to distract us, it's fair to say that a number of high-profile transfers have not been given the airtime they would have usually received. With one month go until the new Premier League season begins, however, the focus has now switched to the upcoming campaign and the new arrivals set to grace England's top flight.

WhoScored.com ran the rule over the big-money signings that have already been sealed -- with England's top teams having raided La Liga thus far -- to suggest just how much of an impact each will have with their respective new clubs.

Alexis Sanchez (Arsenal) -- 2013-14 WhoScored.com league rating -- 7.52

Arsenal may not have been expecting to complete such a high-profile signing again this summer but on the back of an impressive World Cup campaign with Chile, Alexis Sanchez has set fans' pulses racing once more. They will rightly be excited about seeing him line up alongside the likes of Mesut Ozil, Aaron Ramsey and Santi Cazorla next season, and even more chuffed they beat Liverpool to the signature.

On the face of things it could be argued the Gunners are again prioritising positions that are not as important as others, but in truth, the acquisition of the Barcelona ace gives Arsenal an option they have lacked recently. Sanchez's arrival could allow Arsene Wenger to field two up front, with all of the 25-year-old's appearances in Brazil this summer coming from a central position alongside Eduardo Vargas.

His striking statistics from La Liga last season were quite remarkable, netting 19 goals from just 66 shots. A conversion rate of 28.8 percent is a significant improvement on Arsenal's best from last season (Ramsey, 20 percent) and twice that of top scorer Olivier Giroud's efforts (14.3 percent). Elsewhere, Sanchez also picked up more league assists than any Arsenal player (10), and he's hard-working to boot, averaging more tackles per game than the likes of Mathieu Flamini and Jack Wilshere last season (1.7). With the ability to play in a variety of positions across the attack, Sanchez's signing may have more of an impact than that of Ozil last year.

Diego Costa (Chelsea) -- 2013-14 WhoScored.com league rating -- 7.39

If there's one thing Chelsea have lacked in recent seasons it's a clinical finisher. The likes of Fernando Torres and Samuel Eto'o have passed their peak, and Demba Ba was never the level required. With Jose Mourinho clearly reserving judgment on Romelu Lukaku, the Portuguese has got his wish after completing the signing of Diego Costa.

With 35 goals in 44 appearances in the league and Champions League last season, the fiery front man will be expected to lead Chelsea back to the summit. A conversion rate of 25 percent in La Liga for eventual champions Atletico Madrid blows the efforts of the Blues' strike force last season out of the water (Ba, 16.1 percent; Eto'o, 15.3 percent; Torres, 8.2 percent). His individual league tally of 27 was eight more than the Chelsea trio managed between them. Given that Mourinho's side finished just four points but 41 goals behind champions Manchester City, the Special One will hope to have remedied such a glaring issue.

There are concerns Costa won't contribute enough to the team, but his seemingly meagre tally of three assists last season was a little misleading, given he created 45 chances over the course of the campaign.

If the newly adopted Spain international can keep his head -- he's sure to get a "warm welcome" from centre-backs in England's top-flight -- he could become a fan favourite.

Cesc Fabregas (Chelsea) -- 2013-14 WhoScored.com league rating -- 7.31

The 27-year-old is a true creator, but crucially for the Chelsea boss, one who is more willing to put in a defensive shift than ex-Stamford Bridge star Juan Mata. The Spaniard has earned a strength of "defensive contribution" from WhoScored.com, courtesy of an average of 1.3 tackles per game last season.

Fabregas has amassed 56 assists over the past five league seasons and is capable of putting chances on a plate for teammates. His tally of 13 assists last season was six more than any Chelsea player, and the playmaker completed 24 accurate through balls; eight more than any other player in Europe's top five leagues. He may well pull the strings from deep alongside Nemanja Matic but is more than capable of playing the No. 10 role or even as part of a front three.

Like the Sanchez acquisition at Arsenal, Fabregas' arrival not only adds a world-class player to the ranks but also the option to deviate from what has become a pretty regular 4-2-3-1 formation at the Bridge. With a potent striker to now finish the chances that Chelsea create -- set to soar following Fabregas' inclusion in the mix -- the Blues look to have stolen a march on their Premier League title rivals.

Ander Herrera (Manchester United) -- 2013-14 WhoScored.com league rating -- 7.38

The central midfield area, formerly one of the great strengths at United in the days of Roy Keane and Paul Scholes, has been a problem position for the club in recent years. Marouane Fellaini's arrival didn't exactly have the desired effect last season -- to put it mildly -- while Tom Cleverley has failed to develop. A fresh face was required, and few are fresher than that of Ander Herrera.

At just 24, the Spaniard has already amassed 138 La Liga starts, and he proved to be a leader on and off the pitch at Athletic Bilbao. He's an impressive all-rounder in the middle of the park. Often deployed in an advanced role last season, he still put in an outstanding shift for his team, with an average of 3.1 tackles per game, ranking top for Athletic, and also greater than any United player in the previous campaign.

He'll likely be deployed deeper for Manchester United under new manager Louis van Gaal but will still carry a threat. Herrera netted five times and picked up five assists in La Liga last season while between them, Fellaini, Carrick, Fletcher and Cleverley managed just two goals and 1 assist. Such a woeful return from midfield was a key issue in the plight of the club and under David Moyes. The arrival of Herrera adds real quality where it was so desperately needed.

All statistics courtesy of WhoScored.com, where you can find yet more stats, including live in-game data and unique player and team ratings.