Sushil, who had bagged a bronze in the 2008 Beijing Games, became the first Indian athlete to notch up back-to-back Olympic medals with silver on the final day of competitions in London on Sunday.
"Sushil has done us proud by winning India its second silver medal. We are proud of his dedication, commitment and effort. Well done Sushil!!", tweeted Tendulkar. "Sushil showed the size of his heart today and his mental strength of a world champion. Najafgarh ka Sher. Extremely proud of you bhai :)," added Sehwag, a friend of the unassuming Delhi wrestler who competes in the 66kg freestyle event.
Another star cricketer who congratulated Sushil was Yuvraj Singh, who will return to international action in September's Twenty20 World Cup after recovering from a rare germ cell cancer.
"Congratulations to sushil kumar!! First indian to win back to back individual medals! a hallmark of a great athlete!!" he said.
Joining Yuvraj was Suresh Raina, who said, "Sushil's silver is no less than Gold. What a fighter! Heard he was dehydrated before his fight. Great feat to win at consecutive Olympics."
The 29-year-old Sushil, who was India's flag-bearer in the opening ceremony, lost to Japanese Tatsuhiro Yonemitsu in the gold-medal bout.
With the addition of Sushil's silver medal, India completed their engagements in the 30th edition of the Olympics with a record haul of six medals - two silver and four bronze - but the gold medal could not be won by anyone.
In Beijing, India had won one gold and two bronze medals.