Consistently spoken of as among the favourites, both have progressed beyond the league stage in three out of four seasons since 2009, but don't have the silverware to show for such consistency.
Both teams will start their IPL VI campaigns with key players missing when they face off at M Chinnaswamy Stadium in Bangalore on Thursday (April 4). Bangalore will be without AB de Villiers, who would have walked into the team, but is doing duty for Nashua Titans in South Africa's domestic Twenty20 tournament. Also missing will be Zaheer Khan, who Virat Kohli, the Bangalore captain, said was "about 70 to 80 percent fit" on Wednesday, the eve of the match, and is likely to be "ready to go in about a couple of games".
Mumbai, meanwhile, will be deprived of the services of Lasith Malinga, the spearhead of the attack, who is nursing a sore back. Malinga is still in Sri Lanka and will reach Mumbai only on Friday to link up with the squad members still there. "We're just hoping for a speedy recovery, and hopefully he'll be okay for game three," said Ricky Ponting, the Mumbai captain.
With major match-winners missing and new captains on either side, both teams will enter the contest with a fresh look.
In Kohli, Bangalore have as captain the man who could well be the heir to Ponting in international cricket. Like Ponting, Kohli was young when he made his international debut, is brash and unafraid to play hard, is spoken of as a future international captain and, most importantly, possesses exceptional batting ability.
As they have done for much of the last two seasons, Bangalore will bank on their top-order batting strength. Chris Gayle looms, reassuringly for his team and menacingly for opponents, at the top of the order. De Villiers' absence will mean that Arun Karthik is likely to don the wicketkeeping gloves for Bangalore. It also opens up one of the four foreign player slots in the line-up. Tillakaratne Dilshan, the most pedigreed foreign batsman in the team after Gayle and de Villiers, should partner Gayle at the top of the order, while one of Muttiah Muralitharan and Ravi Rampaul could be picked as a specialist bowler, and an allrounder could come in from among Daniel Vettori, Andrew McDonald, Moises Henriques and Dan Christian.
Mumbai's foreign picks will also demand some thought. With Malinga unavailable, Mitchell Johnson could make his IPL debut, while Ponting and Kieron Pollard will slot in automatically. The final slot could well go to an allrounder, with a greater premium on batting skills than bowling, since Mumbai's bowling attack has a well-rounded look to it even without Malinga, with Munaf Patel, Harbhajan Singh and Pragyan Ojha slotted in.
Bangalore's Indian bowling contingent doesn't look as healthy in comparison. Although Bangalore went into a slightly inexplicable seamer-buying spree during the 2013 player auction, most of the pacers in the squad look more like support bowlers and not leaders of the attack. Given that Zaheer is also unavailable, the lack of penetration against Mumbai's batting could prove decisive.
Injuries and fitness apart, Mumbai's only concern could be the top-order batting. Mumbai could see a Sachin Tendulkar-Ricky Ponting opening partnership if there's a full game, and while the idea is a mouth-watering one, both men are in the twilight, rather than the prime, of their fabulous careers. There is little doubt that both will still be able to dominate bowlers, but whether they can explode in the Power Play overs or not remains to be seen.
Mumbai do have the advantage of Anil Kumble as the chief mentor. Kumble, who spent the past five years in the IPL with Bangalore first as player and then as mentor, will doubtless have considerable inside knowledge to share on how best to tackle Bangalore's main men. However, the final say in what is a potentially enthralling match could well come down to Bangalore's unpredictable weather. Rains have lashed the city in the week leading up to the match, and the forecast for Thursday is for partly cloudy skies.
If history is anything to go by, Mumbai will want a full match. They have played Bangalore four times at Chinnaswamy Stadium and won each time. History, however, might not count for much if Gayle gets going. Last season, Gayle showed a complete mastery over his game, taking time to gauge the conditions and the opposition before taking off in typical fashion. That explosion from Gayle is what a packed stadium will be hoping to see on Thursday.
Royal Challengers Bangalore: Virat Kohli (capt), Mayank Agarwal, KP Appanna, Arun Karthik (wk), Sheldon Jackson, Murali Kartik, Zaheer Khan, Abhimanyu Mithun, Abhinav Mukund, Karun Nair, Pankaj Singh, Prashanth Parameswaran, Harshal Patel, Cheteshwar Pujara, Sandeep Warrier, RP Singh, Sunny Sohal, J Syed Mohammad, Saurabh Tiwary, Jaidev Unadkat, Vinay Kumar, Vijay Zol, Christopher Barnwell, Daniel Christian, Tillakaratne Dilshan, Chris Gayle, Moises Henriques, Andrew McDonald, Muttiah Muralitharan, Ravi Rampaul, Daniel Vettori.
Mumbai Indians: Ricky Ponting (capt), Aiden Blizzard, Nathan Coulter-Nile, James Franklin, Phillip Hughes, Mitchell Johnson, Glenn Maxwell, Jacob Oram, Kieron Pollard, Dwayne Smith, Abu Nechim Ahmed, Amitoze Singh, Yuzvendra Chahal, Rishi Dhawan, Harbhajan Singh, Dinesh Karthik (wk), Dhawal Kulkarni, Sushant Marathe, Pragyan Ojha, Akshar Patel, Munaf Patel, Ambati Rayudu, Jalaj Saxena, Rohit Sharma, Pawan Suyal, Aditya Tare (wk), Sachin Tendulkar, Suryakumar Yadav.