Keres always interested me. I think his figures would have been even more impressive, if he hadn't been pressurised to lose or draw games against other Soviet GM's.
Bobby Fischer vs. the USSR

Keres always interested me. I think his figures would have been even more impressive, if he hadn't been pressurised to lose or draw games against other Soviet GM's.
I agree. Just the other day, I read a story about a Russian GM (can't recall his name) [UPDATE:I just found the article on Wikipedia. The player was FEDOR PARFENOVICH BOHATIRCHUK. In his autobiography, Bohatirchuk mentioned that just after his last game with Botvinnik, the head of the Soviet chess delegation, Minister of Justice Nikolai Krylenko, approached him and said: "You will never beat Botvinnik again!" That was indeed the case as Bohatyrchuk never played Botvinnik again, leaving him with a lifetime score of (+3 =1 –0) against the future world champion.] I think he got the hint, it wasn't a prediction, it was a command!
Did you know that Keres holds the record for beating more World Champions than any other player (nine). In his long illustrious career he beat Capablanca, Alekhine, Euwe, Botvinnik, Smyslov, Petrosian, Tal, Spassky and Fischer. That's everybody who held the title between 1927 and 1975. He only faced Karpov twice, drawing both times.
If you ever get to Estonia, you too can sit across the board from Paul Keres.

I think he shares that distinction with Korchnoi and Beliavsky. He would have made a good World champion.

I think he shares that distinction with Korchnoi and Beliavsky. He would have made a good World champion.
According to Chessgames.com, Botvinnik and Korchnoi met four times between 1952 and 1960, with an even score of +1=2-1. Chessgames.com doesn't show any games between Botvinnik and Beliavsky, but the listings may not be complete.
Against Botvinnik, Keres compiled a record of +3=9-8.

On Keres wikipedia page, it says he defeated nine World champions, along with Korchnoi and Beliavsky. It maybe a mistake?

You're right, Keres had a +1=0 record against Beliavsky and a +4=2-1 record against Korchnoi, according to the Chessgames.com database.

Did Keres not also suffer the disapprobation of Soviet officials by playing in Nazi-organized tournaments during WWII? According to Chessbase.com:
The reason that Keres never played for the crown is shrouded in mystery. He participated in eight candidates events and came second in four of them. The turmoil of World War II and the annexation of his small country Estonia by the Soviet Union certainly played a role in keeping him from reaching the very top. Keres had participated in German tournaments during the war, and when the Red Army liberated the country, Soviet authorities planned initially to execute him. Botvinnik interceded by talking to Stalin and Keres was spared.
http://en.chessbase.com/post/remembering-paul-keres
Here’s a comparison of eleven of the strongest GM’s of the post war era (1948-1972). Ten top Soviet players versus Bobby Fischer, and each other.
The table below summarizes how each player scored against the other ten, detailing the percentage of overall wins, losses, draws, and winning percentages, calculated as: (Wins + Draws/2) / Total Games. If anyone is interested, I have a complete breakdown of how each player faired against each of the other ten.
The results are interesting, with the exception of Taimanov with a winning percentage of 43.7%, all of the other Soviet players had winning percentages close to 50%. Korchnoi was the highest Soviet GM with 52.4%. In comparison, Bobby Fischer had a winning percentage of 57.0%. He also had the highest percentage of wins (33.8%) and the lowest percentage of draws (46.5%), which is right in line with Bobby’s personality. Always a fighter, who wanted to crush his opponents (especially the Russians), he would rather press for a win than take an easy draw.
Fischer’s accusation that the Russians were cheating by agreeing to easy draws amongst themselves in international competitions (and helping to analyze each others' adjourned games) is a fact that was later confirmed by Spassky, Korchnoi and others. Apparently, their drawing percentages were lower when playing in Soviet-only tournaments.
DISCLAIMER: all statistics were taken from the Chessgames.com website.