Harry Kane has netted 22 Premier League goals as the Lilywhites chase a first league title since 1961, whereas Alli, in his first season at White Hart Lane, has emerged as one of Europe's hottest properties after scoring seven times and setting up 12 in all competitions.
In defence, Alderweireld, who joined from Atletico Madrid last summer, has forged a solid partnership with compatriot Jan Vertonghen, as well as Kevin Wimmer, while Dier looks to have flourished in an initially unfamiliar defensive midfield role.
Being a defender, King, who spent 13 years with the North London club, acknowledges Kane and Alli's contribution, but the 35-year-old cannot help but feel most impressed by what has gone on in the engine room this season.
“Obviously Dele [Alli] has been great and Harry has again scored over 20 goals, but for me Toby Alderweireld, in his first season at the club, and Eric Dier, in his first season as a midfielder, have been the stand-out players for this season," he said on talkSPORT.
He added that Spurs' come-from-behind 1-1 draw at Liverpool on Saturday meant that Mauricio Pochettino's troops had the mental strength needed to last the course in the title race, with Leicester City seven points ahead of them ahead of the final six games of the season.
"The Liverpool performance was a very good one - to be able to bounce back so quickly from the setback of going 1-0 down shows the mental strength of the team. It stands us in good stead for the rest of the season," King added, quoted by Sky Sports.
The Lilywhites might just need all of that mental strength on Sunday. Leicester, who face Sunderland away at 1.30pm, would move 10 points clear of Spurs with a victory, piling the pressure on Pochettino and co for the visit of Manchester United at 4pm.