Neuer, 35, has been in outstanding form once again this season, with Bayern boasting the second-best defensive record in the Bundesliga, with just 11 goals conceded in as many games, and the best record in the UEFA Champions League with just two goals conceded and three clean sheets.
He is also one of only 13 players with over 100 caps for Germany and helped Die Mannschaft march through qualifying as the first nation other than hosts Qatar to qualify for next winter's FIFA World Cup.
He has fought his way back from two serious foot injuries, but is looking as good as ever, and Nagelsmann has no doubt that he will continue to be the best in the business for many years to come.
"We have the best goalkeeper in the world and we're really happy with him," Nagelsmann said. "I would not want to take him out of our goal for as long as he is fit and still wants to play.
"The way I know Manu, he's not the sort who would voluntarily sit out any game, and he's 99.9 per cent fit."
Nagelsmann has been able to rely heavily on his No.1 and captain this season, and his performance in their last game before the international break only confirmed how important he is to the club.
"In my eyes, he's still without a shadow of a doubt by far and away the best goalkeeper in the world," Nagelsmann said after Matchday 11's 2-1 win over Freiburg. "He's outstanding with his feet and we saw again today how extraordinary he was in saving their free-kick, which would otherwise have been an equaliser.
"I was really looking forward to working with him because I'd only ever seen him in games against Bayern and on TV and I was curious to see how lively and active he is. He's a similar age to me and he's incredibly fast and incredibly reactive. You would never in a million years guess that he's 35.
"He's got an extremely positive character and is always active. He's already saved us points many times this season and that's why he's still the best goalkeeper in the world."
Neuer is recognised as having transformed the role of the goalkeeper since emerging with his more involved style of goalkeeping.
Speaking to BBC Radio, former Bayern teammate and fellow World Cup winner with Germany in 2014 Bastian Schweinsteiger showed no hesitation in naming Neuer as the best player he had ever played with.
"He changed the game so much and when you have him behind you in goal, you can create a different kind of game," Schweinsteiger said. "First of all he's a good goalkeeper, and then he's a great footballer.
"He's so fast - he was faster than me. With him at the back, you could just play higher up the field - you knew there was a man behind you who could just play as a sweeper or the last man, and he dribbles sometimes against strikers and it's incredible.
"He does amazing things with his hands and can throw like 50 yards into the feet of [Arjen] Robben, for example.
"For as long as Manu Neuer keeps playing, he will be the best in the world."
That looks likely to be many more years to come, with Neuer showing no sign of loosening the velcro on his gloves and abdicating from his position as the best goalkeeper on the planet.