After the completion of the zonal level league matches, all the top teams from the five zones entered into the knock out level of the tournament and vied for the championship trophy. The knock out level of the Ranji Trophy, 1972-73 saw the participation of the teams like Bihar, Madhya Pradesh, Bombay, Bengal, Maharashtra, Vidarbha, Tamil Nadu, Railways, Hyderabad and Delhi. They played against each other in the Pre-Quarter-Finals, Quarter-Finals, Semi-Finals and Final of the tournament and the Bombay team eventually became successful to clinch the title, once again.

The first Pre-Quarter-Final match of the Ranji Trophy, 1972-73 was held at Jamshedpur from 03-05 March, 1973 between the teams of Bihar and Madhya Pradesh. Though the match was drawn during the stipulated duration, the match officials allowed the Madhya Pradesh team to advance to the Quarterfinal stage of the tournament. The teams of Maharashtra and Vidarbha played against each other in the second Pre-Quarter-Final match of the Ranji Trophy, 1972-73 that was held at Poona from 03-05 March, 1973. The Maharashtra team won the match by a margin of an innings and 117 runs and also entered into the Quarter-Finals of the tournament.

There was a clash between the teams of Tamil Nadu and Railways in the first Quarter-Final match of the Ranji Trophy, 1972-73 and the match took place at Madras from 16-18 March, 1973. The match saw the Tamil Nadu team winning by a margin of 110 runs and entering into the Semi-Final stage of the tournament. The second Quarter-Final match of the Ranji Trophy, 1972-73 involved the teams like Maharashtra and Bengal and the match took place at Poona from 23-26 March, 1973. The Maharashtra team played well in the match and clinched a victory of 9 wickets for securing a birth in the Semi-Final stage of the tournament. The third Quarter-Final match of the Ranji Trophy, 1972-73 was played between the teams of Hyderabad and Delhi at Hyderabad from 23-26 March, 1973. The match saw the Hyderabad team winning by 196 runs and entering into the Semi-Finals of the tournament. The last Quarter-Final match of the Ranji Trophy, 1972-73 saw a battle between the teams of Madhya Pradesh and Bombay at Indore from 24-26 March, 1973. The Bombay team played wonderfully in the match and proceeded towards Semi-Finals, by winning the match by 9 wickets.

In the first Semi-Final match of the Ranji Trophy, 1972-73, the teams like Maharashtra and Tamil Nadu clashed with each other at Poona from 06-08 April, 1973. The match was a closely contested one and it saw the Tamil Nadu team eventually clinching a victory of 24 runs for getting into the Final of the tournament. The teams of Bombay and Hyderabad met with each other in the second Semi-Final match of the Ranji Trophy, 1972-73 and the match was held at Bombay from 08-11 April, 1973. The Bombay team once again played well in this match and defeated the Hyderabad team by 8 wickets for setting up a Final clash with the Tamil Nadu team. Thus, the Final line-up of the Ranji Trophy, 1972-73 was Bombay Vs Tamil Nadu and the match took place at Madras from 18-20 April, 1973. Though, the Tamil Nadu team tried hard, it failed to restrain the Bombay team from winning the match by 123 runs and also from winning the championship trophy for yet another time.