The summer window has been a success for the Eagles so far and a breath of fresh air to the fans who have been begging for early business to be done for many transfer windows.
Guehi is now part of the new Vieira era and looks like a promising young prospect, and VAVEL Crystal Palace takes a look at the qualities he will bring to an already-experienced defence.
Youth in Palace's defence
It is no secret that when Roy Hodgson managed Palace, the big problem was the ageing squad, and the Eagles never seemed to be working towards reducing the average age of the squad.
However, the big rebuild Palace fans were promised has been taken very seriously with the likes of Scott Dann, Wayne Hennessey, James McCarthy, and Patrick Van Aanholt showed the door due to age and simply not being good enough for the level where Palace want and need to be.
The addition of Olise and Guehi bring the age down in a squad that already has youngsters such as Tyrick Mitchell, Nathan Ferguson and Eberechi Eze, as well as the talented academy youngsters who will soon break into the first-team.
Success from a young age
Guehi joined Chelsea at just eight years of age and was quickly noticed because of his quick progression, improving at an impressive speed in the eyes of academy coaches.
The now 21-year-old was part of a famous treble-winning U18 team back in the 2016/17 season and earned recognition as a goalscoring defender who would not let any forward past him.
The former Blues defender has also played for England from U16 to U21 level and was a key figure for the Three Lions in their U17 World Cup victory, scoring against Spain in the final in a 5-2 win playing alongside Palace academy graduate Nya Kirby.
Just a few months later, in January 2020, Swansea City secured a loan move for Guehi, and he had his breakthrough last season. HE CAME very close to helping the Jacks return to the Premier League, falling short with a 2-0 loss to Brentford in the Championship play-off final.
Ball-play and speed
These are two things that were lacking from Palace's defence last season, and Vieira has quickly identified this problem and looks to have solved it with the signing of Guehi.
When playing for Swansea City and Chelsea, Guehi was hailed for his ability to recover quickly whenever a mistake was made, as well as play the ball out of defence to start an attack for his team.
Last season, Guehi completed 1537 passes and attempted 1993. His eye to pick out the run of a striker, or give the ball to the playmaker, is second to none and something that new acquisition Olise, as well as Eze, can benefit from.
Another problem last season for the Eagles was whenever there was a mistake, it usually ended in a chance for the opposition or conceding a goal. With Guehi, the defence will be more of a surety and the pressure on in-form keeper Vicente Guaita can be eased.
Great awareness and an eye for a tackle
In 43 Championship appearances for the Jacks, Guehi attempted 83 tackles and completed 70 successful tackles giving the young defender a tackle success rate of 84%.
The statistics speak very highly of Guehi and brings a sense of expectation that he will be the right fit for Palace in a bid to stop leaking goals at the back.
For his age, his reading of the game goes beyond his years, and his tackling statistics highlight that point clearly. His fierce approach in defence, as well as the ability to play out from the back, will get Palace fans excited to see him play.
With other business still in the works, the credit behind the scenes will go out to Dougie Freedman, Vieira and chairman Steve Parish as a new era beckons in South London that predicts a positive road ahead.