Jorginho
Chelsea beat Manchester City to the signing of Jorginho this summer, snapping up the Napoli midfielder for £57 million.
The 26 year old - who followed coach Mauricio Sarri from Naples to London - excelled on his debut against Huddersfield on Saturday, and scored his first Chelsea goal from the penalty spot.
Jorginho pulled the strings for Chelsea in midfield, and boasted a pass percentage rate of almost 94% against the Terriers.
His excellent distribution and vision will be crucial to the style which Sarri will hope to implement at Stamford Bridge, and Chelsea fans will be feeling very excited about the Brazilian midfield maestro after his promising debut.
Kepa Arrizabalaga also made his Chelsea debut, producing a fine performance and keeping a clean sheet in the process.
The 23 year old was signed to replace Thibaut Courtois for £71.6 million, and will be hoping to build on his solid debut.
Naby Keita
Liverpool fans have waited a long time to see Naby Keita in a red jersey.
The early signs suggest that the 23 year old was worth the wait.
Keita, a dynamic central midfielder, made his competitive debut for the Reds in their 4-0 mauling of West Ham on Sunday. The Guinean international was heavily involved in the game, and played an excellent pass to Andy Robertson in the buildup to Mohamed Salah's opener at Anfield.
Keita - who can play in a variety of midfield roles - will bring dynamism and creativity to Jurgen Klopp's midfield, and the former Leipzig star is also an excellent ball-winner.
Liverpool's new goalkeeper Alisson also made his Premier League debut against the Hammers, keeping a clean sheet as the Reds won comfortably.
New midfielder Fabinho (another player to watch) was an unused substitute, while Xherdan Shaqiri came off the bench to make his first appearance for the Merseyside club.
Yerry Mina Yerry Mina was linked with a host of big clubs after starring for Colombia at the World Cup. The towering centre half scored three goals for the South American nation, including a stoppage time header against England in the last 16. Everton snapped up the 23 year old from Barcelona for around £27 million, in a deal which could prove to be one of the bargains of the summer. Signing a player off the back of an impressive international tournament can be dangerous, but adapting to the physicality of English football shouldn't be an issue for Mina. With Everton Phil Jagielka being sent off on the opening day, Mina is likely to step into the Toffees' defence to replace the skipper this weekend. Fans of the Merseyside club will be eager to see their imposing new defender in action. Everton enjoyed an excellent Deadline Day, snapping up Lucas Digne, Kurt Zouma (on loan), Bernard, and Andre Gomes. Eyebrows were raised when Marco Silva forked out £50 million for Watford winger Richarlison, but the talented Brazilian quickly made his mark on Saturday with a brace against Wolves.
Felipe Anderson
On paper, West Ham have had an impressive transfer window.
The Hammers have brought in the likes of Jack Wilshere, Ryan Fredericks, Andriy Yarmolenko, Lukkasz Fabianski, and Felipe Anderson.
Anderson was signed from Lazio for a club record £36 million, and arrives to England with a strong reputation.
The Brazilian winger made his Premier League debut (along with four other summer signings) in West Ham's 4-0 defeat to Liverpool at Anfield, but showed glimpses of his potential, and a willingness to work hard defensively.
It was a baptism of fire for the creative winger, who will have better chances to express his attacking dynamism in the weeks to come.
Ukraine international Yarmolenko - another exciting attacking midfielder - is another player to watch, and one who could thrive in Manuel Pellegrini's attacking system.
James Maddison
One of the standout performers in the Championship last season.
The 21 year old cost Leicester around £22 million, and immediately impressed on his debut against Manchester United.
He came close to scoring for the visitors, and registered an impressive 15 goals last season for Norwich.
Claude Puel will be hoping that the underage England international can help to fill the void left by Riyad Mahrez' departure, and the early signs suggest that Madisson will be a key player for the Foxes.
Madisson will be expected to chip in with plenty of goals and assists from midfield, and could be a good addition for Fantasy Football enthusiasts.
Ricardo - who Leicester signed from Porto this summer - looked threatening at times on the right, and Rachid Ghezzal(formerly of Monaco) impressed during his cameo off the bench.
Alireza Jahanbakhsh Brighton spent a club-record £17 million on Iranian attacking midfielder Alireza Jahanbakhsh. The 25 year old was the top scorer in the Eredivisie last season, netting 21 goals in just 27 appearances for AZ Alkmaar. This made him the first Asian player to become the top goalscorer in a top-level European league, and he also registered 12 assists in the Dutch league. He impressed off the bench for Brighton against Watford, and can play on either wing or as a central attacking midfielder. Signing players from the Eredivisie can be a risk (see Afonso Alves), but Jahanbakhsh certainly has the quality to greatly improve Brighton's attacking options. Fellow new signing Bernardo struggled against the Hornets at Vicarage Road, while Yves Bissouma was lively following his introduction.
Fred
It was a frustrating transfer window for Manchester United, but the Red Devils did manage to get a deal done for Fred.
United spent £52 million to lure the Brazilian international to Old Trafford, and the former Shaktar Donetsk star arrives with a stellar reputation.
The combative midfielder made his debut against Leicester on Friday night, and has all the attributes to be a star Jose Mourinho midfielder.
Fred is athletic, powerful, aggressive, and should slot perfectly into Mourinho's preferred 4-3-3 formation.
The 25 year old can operate either as a box-to-box midfielder or in a holding role, and could greatly enhance United's midfield options, as well as offer more freedom to a resurgent Paul Pogba.
He was quietly impressive in the Red Devils' 2-1 win over Leicester, boasting a pass success rate of 92%.
Jannik Vestegaard
New signing Jannik Vestegaard caught the eye on his Southampton debut against Burnley.
The dominant centre back, signed for £18 million from Borussia Mönchengladbach., produced an assured performance for the Saints, and displayed his aerial prowess on numerous occasions.
He made 12 headed clearances against the Clarets, and will be an effective asset in both boxs for Mark Hughes' side.
The 26 year old towering defender - who is 6"6 - scored seven goals in the Bundesliga in 2017 (more than any other defender), and he is also comfortable with the ball at his feet.
Vestegaard was noticeably vocal on the pitch, and will be aiming to build on his solid start at the club.
Jean Michaël Seri
Fulham's capture of Jean Michaël Seri represents one of the coups of the summer.
The former Nice midfielder has been linked with most of Europe's top clubs in recent seasons, and his move to Craven Cottage came as a huge surprise earlier this summer.
The 26 year old - who operates as a powerful box to box midfielder - was on the verge of joining Barcelona last year, and will add huge quality to Fulham's midfield.
The London club had an impressive transfer window, which saw them bring in Andre Schurrle, Luciano Vietto, Calum Chambers, Maxime Le Marchand, Joe Bryan, and goalkeeper Fabri.
Fulham also managed to retain the services of their teenage sensation Ryan Sessegnon, and to make Aleksander Mitrovic's loan spell from Newcastle permanent.
The newly promoted club lost 2-0 at home to Crystal Palace on Saturday, but Seri produced a solid performance in midfield.
Expect him to be one of Fulham's key players this season.
Çağlar Söyüncü The second Leicester City player on the list. The Foxes snapped up Söyüncü from Freiburg for £19 million. The 22 year old centre half is a Turkish international, and had previously been linked with the likes of Atletico Madrid and Manchester City. Söyüncü has earned comparisons to Mats Hummels, and is excellent on the ball. The young defender is a raw talent, and still has plenty to learn, but could forge an excellent partnership with Harry Maguire for the Foxes. The Turkish centre half has yet to make his debut for Leicester, but has the potential to become a key player for Claude Puel's side. Watch this space. Honourable mentions: Jaoao Moutinho (Wolves), Lucas Torreira (Arsenal), Sokratis (Arsenal), Mohammed Elyounoussi (Southampton), Rui Patricio (Wolves).