Here's a breakdown of all the new first-team arrivals to Premier League teams since the end of Week 4, as well as a breakdown of which players may be affected as a result:
Aston Villa - Joleon Lescott, Tiago Ilori (loan)
Lescott's veteran status, along with his experience with former Manchester City teammate and new Villa captain Micah Richards, should see him stake a claim on the starting role at center back in the near future, if not immediately after the international break. His arrival should slightly increase the value of other Villa defenders and Brad Guzan, though Ciaran Clark should be on his way out of your lineup if you picked him up. Hard to see many minutes for Ilori despite his loan move from Liverpool.
AFC Bournemouth - Glenn Murray, Adam Federici
Murray proved in his time with Crystal Palace that he has an eye for goal, and while he most likely will not displace Callum Wilson from the starting lineup, his arrival could signal reduced minutes for Joshua King and Yann Kermorgant. Federici has been a stalwart in goal for Reading FC and poses a real threat to Artur Boruc in goal, though you could be forgiven for playing the waiting game to see if the Cherries manage to up their defensive game before buying in on either.
Chelsea - Papy Djilobodji
With John Stones remaining on Merseyside despite Jose Mourinho's best efforts, the Blues turned their attention to Nantes defender Djilobodji. At just £2.7m, the Senegalese represents a significant bargain compared to the huge sums bandied about for Stones, but it's unlikely the 27 year-old will spend much time in the starting lineup at center back. The defense has struggled mightily in the opening month of the season, however, and the aging John Terry could see his minutes reduced even further.
Everton - Ramiro Funes Mori, Aaron Lennon
The potential departure of John Stones seems to have prompted the Toffees to go out and add another center back to their ranks with Funes Mori. Stones and Jagielka will be a difficult pairing to break up, but if either one is injured or suspended the 22 year-old is a capable deputy. Lennon returns to Merseyside after his successful loan spell last season, and will most likely share time with Everton's oft-injured trio of Kevin Mirallas, Aiden McGeady and Steven Pienaar. Given how often those three are on the treatment table, Lennon could make the starting role his own, and could be of value to fantasy managers after a differential.
Leicester City - Nathan Dyer (loan)
After being pushed to the outskirts of the Swansea squad due to the arrival of Andre Ayew and return to fitness of Jefferson Montero, Dyer has taken the escape hatch northeast to Leicester. The pacy winger could pose a significant threat to Marc Albrighton's starting role, while we've already seen Claudio Ranieri withdraw Riyad Mahrez early in matches. Dyer could provide more pace to an already fast attack, opening up more space for Jamie Vardy and Shinji Okazaki, who could both see their values go up if Dyer earns a starting role.
Manchester City - Kevin De Bruyne
Almost certainly the marquee signing of the late window, De Bruyne is one of a handful of players who can walk straight into the starting lineup for Man City. His arrival will most likely see Jesus Navas reduced to a bench option, which probably isn't too much of a detriment considering the Spaniard hasn't been the greatest fantasy producer. De Bruyne's addition makes an already formidable attack truly terrifying. All City attackers should benefit from being double teamed less often as opposition defenses will have one more world-class attacker to try to keep up with.
Manchester United - Anthony Martial
I never thought we'd see a more expensive transfer for a youngster than Raheem Sterling's move to the blue half of Manchester, and especially not in the same window, but the Red Devils have gone and outdone their cross-town rivals. With a £36m sign-on fee that could rise as high as £58m, the French teenager will have an unprecedented amount of pressure piled on his young shoulders. Louis van Gaal has stated the former Monaco starlet will need time to get acclimated, but given Wayne Rooney's goal drought and United's lack of other striking options, it's hard to see Martial being given enough time to get his bearings. If Rooney's poor form continues, expect a shakeup in the United lineup that could see the Englishman shift back into the hole and keep the likes of Ander Herrera and Marouane Fellaini rooted to the bench.
Norwich City - Diumerci Mbokani (loan), Matt Jarvis (loan)
The Canaries' struggles at striker have been clear for everyone to see so far this season, with their goals coming primarily from defenders and Nathan Redmond. Mbokani should displace Cameron Jerome at striker and could be a surprise differential. The real value is in opening up more space for Redmond for more attacking contributions. With Robbie Brady slotting in comfortably at left back, he may stay there even when Martin Olsson returns to fitness, so Jarvis could also breakthrough into the starting lineup at left wing and send Graham Dorrans or Jonny Howson to the bench.
Southampton - Virgil van Dijk
Ronald Koeman has been on a mission to replace the rearguard for the Saints and has brought in his final piece on deadline day, signing van Dijk from Celtic for £11.5m. The center back's arrival casts doubts over the likes of Maya Yoshida and another new arrival, Steven Caulker. It will be interesting to see if Koeman goes with the 3 CB approach he used briefly a couple weeks ago, or if he'll stick with a more traditional four-man defense. It's all a bit of a waiting game at the moment as we wait to see how things shape up for the Saints, so be wary of investing in their defenders for the time being.
Sunderland - Fabio Borini, Ola Toivonen, DeAndre Yedlin (loan)
A year on from registering their interest in bringing Liverpool forward Fabio Borini to Wearside, the Black Cats finally have their man. Something of a cult hero at Sunderland, Borini will be an instant starter and should be looked to as a bargain pick. Toivonen and Yedlin fall a bit more into the questionable category. Toivonen did see time off the bench in Week 4, but it remains to be seen whether Dick Advocaat will use him as a striking option off the bench or an attacking midfielder from the start. Yedlin is a promising, pacy fullback and could displace Billy Jones at the right back spot, though his defensive qualities are suspect and led to him not getting a look in at Tottenham other than as a winger.
Tottenham Hotspur - Son Heung-min
While Spurs missed out on a number of their targets, including Saido Berahino and Victor Wanyama, they did land a major coup with the capture of Korean striker/winger Son, who arrives from Bayer Leverkusen. The 23 year-old won't be competing with Harry Kane for the striker role, but rather should be deployed as a winger. This will most likely see Mousa Dembele dropped from his right midfield role to see an attacking midfield trio of Son, Christian Eriksen and Nacer Chadli. Son will be a strong fantasy play, and he should help create some more chances for Kane to get back to his best.
Watford FC - Adlene Guedioura, Victor Ibarbo (loan)
While Guedioura will bring some proven Premier League experience to Watford, he won't be a relevant fantasy performer. Ibarbo is the jewel here. The 25 year-old Colombian striker will bring pace and power to the Hornets attack to go along with Troy Deeney. Expect the strong Watford defense to get some relief from more attacking options.
West Bromwich Albion - Jonny Evans, Anders Lindegaard
Tony Pulis has drafted in two Manchester United fringe players in an attempt to bolster the Baggies rearguard. Evans probably has the better chance of starting, and could replace Gareth McAuley, though Lindegaard has rarely had the opportunity to display his quality at United and could challenge Boaz Myhill. Expect Pulis to get his defensive strategy back on track, so whoever establishes themselves as starters will be better fantasy options going forward.
West Ham United - Alex Song, Victor Moses, Nikica Jelavic (all loan)
The Hammers did some great work to close the window, bringing in three experienced, necessary players on loan. Song was an excellent addition anchoring the midfield last season and returns from Barcelona again to claim his role in the starting lineup, likely at the expense of Pedro Obiang and Reece Oxford. Chelsea midfielder Moses was a great fantasy option on loan at Stoke City last season and should continue in that vein for West Ham, with Manuel Lanzini perhaps making way. Jelavic will help provide some depth to an injury-ravaged attack, though he may struggle to break into the starting lineup unless Diafra Sakho misses out.
Which late-in-the-window deal are you most excited about from a fantasy perspective? Who are you worried about losing some of their scoring power? Weigh in with your thoughts in the comments!