Undeterred by an on-court intruder, Federer beat surprise finalist Soderling 6-1, 7-6 (1), 6-4 Sunday to complete a career Grand Slam and win his 14th major title, matching Sampras' record.
On his fourth try at Roland Garros, Federer became the sixth man to win all four Grand Slam championships.
"Now the question is: Am I the greatest of all time?" Federer said. "We don't know, but I definitely have many things going for me because I've finally won all four Grand Slams, and I'm particularly happy reaching Pete's 14."
When the stylish Swiss hit a service winner on championship point, he fell on his knees to the clay that had vexed him for so long, screamed and briefly buried his face in his hands. He was teary by the time he met Soderling at the net, and fans gave Federer a standing ovation as he raised his arms in triumph.
"It's maybe my greatest victory, or certainly the one that removes the most pressure off my shoulders," Federer said. "I think that now and until the end of my career, I can really play with my mind at peace and no longer hear that I've never won Roland Garros."
Tears ran down Federer's cheeks as the Swiss national anthem played.
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Federer cries again, but tears of joy this time