Goalkeepers are the last line of a team's rearguard, which is why mistakes from them often result in goals.It's a common adage that goals win games, but a good defense and a quality goalkeeper help win titles and championships. With this in mind, more and more teams have invested in world-class custodians, and reaped rich dividends.Most successful teams in Europe's top five leagues have quality goalkeepers. Some notable examples in this regard are Bayern Munich's Manuel Neuer, Manchester City's Ederson, PSG's Gianluigi Donnarumma and Real Madrid's Thibaut Courtois, among others.While these players continue to be on top of their games, a few other goalkeepers have also excelled in the continent's top five leagues this season. On that note, here's a look at the five custodians in Europe's top five leagues with the highest save % in 2021-22:#5 Aaron Ramsdale - 80.6Aaron Ramsdale has hit the ground running at Arsenal.Eyebrows were raised when Arsenal splashed €28 million to land Aaron Ramsdale from relegated Sheffield United last summer.However, the 23-year-old has proved his naysayers wrong with a string of calm and composed performances. Ramsdale has usurped Bernd Leno as the club's No.1.Squawka Football@SquawkaAaron Ramsdale has now kept more clean sheets (5) than he has conceded goals (4) in the Premier League for Arsenal.And he's still unbeaten. 9:26 AM · Nov 7, 202184271151Aaron Ramsdale has now kept more clean sheets (5) than he has conceded goals (4) in the Premier League for Arsenal.And he's still unbeaten. 🙌 https://t.co/VjCw7RBWTiIn 17 league games this season, the young custodian has kept an impressive nine clean sheets while conceding 16 goals. That has helped the Gunners recover from a torrid start - losses in their first three games of the season - to seventh place. However, they have two games in hand over fourth-placed Manchester United.Note: Stole Dimitrievski of Rayo Vallecano (La Liga) also has a save % of 80.6 this season.#4 Edouard Mendy - 81Edouard Mendy has been a revelation for Chelsea.Edouard Mendy has been a breath of fresh air since his arrival at Chelsea in the summer of 2020.The Senegalese was an instant upgrade on the error-prone Kepa Arrizabalaga. Mendy helped Chelsea to the Champions League title last season, and has also played a key role for them in the Premier League.The shot-stopper recently made his 50th appearance in the English top flight, where he has kept 24 clean sheets. However, only eight of them have come this campaign, as Mendy has appeared uncharacteristically fallible.ESPN FC@ESPNFCEdouard Mendy has exactly the same clean sheet record as Petr Cech after 60 Chelsea games 🤚12:00 PM · Nov 24, 2021209772169Edouard Mendy has exactly the same clean sheet record as Petr Cech after 60 Chelsea games 🤚 https://t.co/yI0FO6RuMrNevertheless, the 29-year-old remains a key player for Thomas Tuchel, who is enduring a difficult second season at Stamford Bridge.