New Delhi: The fifth round of the 2012-13 Ranji Trophy season gets underway across the country on Saturday, with the previous round having resulted in some thrilling wins. Twelve teams have posted outright wins so far, and at the halfway stage those who have not will need to put in something special to stay afloat. Here's a look at the Group A matches starting December 1. Punjab v Rajasthan at Mohali: Itâs the clash between the defending champions and the team most likely to challenge them for the title. Punjab have won three of four matches by outright margins and with 23 points sit seven clear of their next rivals Assam in Group C. They have been led admirably by 20-year-old Mandeep Singh and success have been spread between bat and ball. Sandeep Sharma and Siddarth Kaul shared nine second-innings wickets between them in the three-day win over Saurashtra last round, and Rajasthan's stiffest task will be to cope with the in-form fast-bowling pair in chilly conditions in Mohali. Rajasthan, with five points from three matches, languish at second from last in Group A and are in dire need of a resurrection. They can look back to last season for inspiration, but action must come on the field. Only three centuries have been scored this season â by the professional pair of skipper Hrishikesh Kanitkar and Rashmi Ranjan Parida and experienced opener Vineet Saxena â and the lack of a big innings rom last yearâs run machine Robin Bist has hurt the side. Pankaj Singh (16 wickets) and Rituraj Singh (13) have bowled admirably but lack support. Conditions overhead and under foot in Mohali could work for the pair if they can exploit them. Mumbai v Bengal at Mumbai: Two middling yet contrasting teams go up against each other at the Brabourne Stadium, on a pitch expected to aid batting. Mumbai have seven points and Bengal six, but the fortunes of both have been contrasting. After three matches, Mumbai have yet to win a match. Their batting remains formidable â Hiken Shah and Abhishek Nayar have two centuries each â but the bowling has not been able to bowl sides out consistently. Witness their previous match against Hyderabad, who piled up 669, their fourth-highest score of all times. Bengal are coming off a 138-run loss to Madhya Pradesh, and must be hurting after becoming the only team in Group A to lose two matches this season. A collapse on the final day in Indore seemed unlikely, with Bengal needing to bat out 58 overs to safe the match. Instead, MPâs attack chipped away and pulled off a big win. The one positive for Bengal was the performance of pace bowler Shami Ahmed who took 11 wickets. Saurashtra v Railways at Rajkot: One point separates Saurashtra (six) from Railways (five) from the same number of matches (three) and going by the history of the pitches in Rajkot, the side that bats first looks set to gain the advantage. Saurashtraâs totals this season read 716 for 3, 260, 270/6, 90 and 233. That first mammoth total gave them three points, but against Punjab they were obliterated. Saurashtra's last seven wickets fell in 32 deliveries during an abysmal first innings and from there they were always playing catch up. Their batsmen too have been inconsistent, barring Sagar Jogiyani who has 480 runs from five innings. Out of a total of 325 runs, 303 came in one innings for Ravindra Jadeja while no other batsman has topped 150 runs this season. And barring Jadejaâs 13 wickets only Siddharth Trivedi with seven â five in one innings â has made much of an impact. Railways are coming off a draw against Gujarat which gave them three points thanks to Sanjay Bangarâs five wickets in the first innings and a strong top-order showing. Unable to force an outright win in three appearances, Railways need to hit form at Rajkot to stay alive in the tournament. Gujarat v Hyderabad at Valsad: Winless in four matches and sitting at sixth on the Group A table, hosts Gujarat will face bottom-of-the-pile Hyderabad. At another run-filled venue, winning the toss and piling up runs remains the route forward for both teams. Parthiv Patelâs team will be smarting from their first-innings collapse to 117 which allowed Railways gain the upper hand in Bhubaneshwar. However, they hit back with 551 for 8 in the second innings and can take confidence from centuries to Manprit Juneja and Rash Kalaria and how they avoided defeat. Hyderabad, after conceding 443 to Mumbai, replied with 669 thanks to Akshath Reddy (196), Hanuma Vihari (191) and Bavanaka Sandeep (117). That should also give them confidence of putting one past Gujarat, but they need more from their bowlers who, apart from Ashish Reddy (12 wickets at 13.66), have failed to strike consistently.