Gerd Mueller paid tribute on Tuesday to Ronaldo after the Brazilian broke the former West Germany striker's World Cup scoring record.
Ronaldo's 15th strike at a finals in the second round match against Ghana eclipsed 'Der Bomber', who held the record after scoring in the 1974 final to take over from Frenchman Just Fontaine.
"Although Ronaldo is now [playing] in his third World Cup, this is nevertheless still a great achievement on his part," Mueller told the FIFA website in an interview.
"Playing at such a high level over such a long period of time, always managing to be fit at the right moment is unusual nowadays.
"In my opinion, he's the best, most complete attacker there is at the moment," added Mueller, who scored his World Cup goals in the 1970 and 1974 tournaments.
Mueller, whose winner in a 2-1 victory over Netherlands in the 1974 showpiece match was fittingly Germany's 100th goal at a finals, had expected his record to be broken this year.
"Even before the tournament started, it was obvious that he [Ronaldo] would get at least two goals and draw level, if not three and set a new record. It wasn't a surprise.
"I've always said that I wasn't the record-holder. That honour, for me, goes to Just Fontaine, who scored 13 goals in one tournament. He's the best in my book."
Fontaine scored his goals at the 1958 finals in Sweden, including four in the third-place playoff match in which his team beat West Germany 6-3.
Ronaldo has been criticised by fans and media alike after a disappointing season at Real Madrid amid accusations that he was overweight but Mueller praised the striker.
"Brazil need Ronaldo, they haven't got anyone quicker than him up front. Ronaldo is still pacy.
"He wasn't on top of his game in the first two [group] matches, but against Japan, he could have got about five goals.
Ronaldo, who was top scorer in the 2002 tournament with eight goals, scored twice in Brazil's 4-1 win over Japan with his second goal equalling Mueller's tally of 14.