Former champions Railways and Sikkim advanced to the quarter-finals while 29-time former champions Bengal began their campaign with a big win in the Santosh Trophy football championship in Delhi on Monday.
While Railways, who last won the title way back in 1966-67 in Hyderabad, topped Cluster III, Sikkim progressed from Cluster VII after beating Pondicherry 4-3.
In the quarter-final league, Railways will play last year's runners-up Kerala on Thursday. The third team in group C will be the winners of Cluster II.
Sikkim, inspired by national captain Baichung Bhutia, now face defending champions Manipur in their first quarter-final league match on Saturday.
The day's other action saw Bihar beat Uttaranchal 3-2, Bengal overpower a fighting Mizoram 5-1, Chandigarh hold Railways to a goalless draw and Tamil Nadu thrashing Nagaland 4-0.
Star outfit Bengal found Mizoram a tough nut to crack and led by a 35th minute Rahim Nabi goal at the end of the first half.
The young Mizoram team, which went down to Andhra Pradesh in their first match, put in a spirited fight before medio Mehtab Hossain scored a fine hat-trick (60th, 73rd, 78th minutes) to propel Bengal home. Skipper Dipendu Biswas scored his team's other goal in the 69th minute.
Earlier, Sikkim became the first team to qualify for the quarter-final league but not before they were given a run for their money by rank outsiders Pondicherry.
The North-Eastern side was expected to have an easy outing against the minnows and hence experimented a bit with the first eleven but the ploy boomeranged as they conceded two goals in the first 26 minutes.
Sikkim, who had won their opening league encounter with an identical scoreline, were forced on the backfoot from the very beginning with Pondicherry attacking their citadel at will.
The constant pressure paid off as hat-trick man Murugan ran past three defenders to slam home a right-footer and give his team the lead in the 17th minute. He then tapped in a brilliant cross by Dussah Sudhacarn nine minutes later to make it 2-0. His third goal came in the 81st minute.
But with Pondicherry players slowing down after half an hour of play, Sikkim began to take control of the midfield and their skipper Sisil Karthak reduced the margin in the 37th minute.
Tashi Rapden equalised from the spot three minutes before the break after his mistimed shot hit the hand of Pondicherry's defender Sassi Kumar inside the box.
Sikkim took the lead immediately after the break as Kamal Bagdas broke the off-side trap and lobbed the ball over the advancing goalkeeper in the 47th minute.
Pondicherry could have earned a penalty within three minutes of conceding the lead but the referee's sight was blocked when a cross by Murugan hit Sonam Pintso Bhutia's hand.
However, Murugan restored parity in the 81st minute with a fine header and also completed his hat-trick.
The match looked like heading for a draw, which would have meant that the Cluster would have been wide open, but national Under-17 captain Ong Tsering Lepcha latched on to a free-kick by Sonam Thendup Bhutia and unleashed a cracking right footer which left the Pondicherry custodian stranded.
Bihar did Railways a big favour by defeating Uttranchal as the result put Railways into the quarterfinals even before the start of their match against Chandigarh.
The inconsequential match ended in a drab goalless draw with play mostly confined to the Chandigarh half. Railways, who scored thrice each in their last matches, never looked like repeating those wins and were happy to top the Cluster with seven points.
Bihar finished second with four points followed by Uttarachal on three points. Chandigarh finished last with just two points.
In Cluster VIII, Tamil Nadu took a big step towards the quarter-finals, thrashing Nagaland 4-0.
Star striker K Kulothungan scored a brace in the 20th and 27th minutes and in the second half M Jegan (58) and P Muthu (75) completed the scoring.
The third team in the Cluster is J and K, who played a goalless draw with Nagaland last Saturday.
