Under the watchful eyes of the ICC's Anti-Corruption and Security Unit (ACSU), the glitzy Champions League Twenty20 starts on Friday with the shadow of the spot-fixing scandal, that has shaken the core of the game, looming large.

Featuring the top three Indian Premier League teams and the top two each from Australia, New Zealand, Sri Lanka, South Africa and the West Indies, the two-week event will open with IPL runners-up Mumbai Indians taking on Highveld Lions (South Africa).

Organisers say the tournament will have strict anti-corruption measures in place to ensure that the menace of spot-fixing, which has led to the suspension of three Pakistani cricketers, does not find a mention in the event.

Apart from Mumbai, the other Indian teams in fray are IPL champions Chennai Super Kings and third-place finishers Royal Challengers Bangalore. Australia will be represented by South Australian Redbacks and Victorian Bushrangers, while South Africa will have the Warriors and Highveld Lions in fray.

Central Stags (New Zealand), Wayamba Elevens (Sri Lanka) and Guyana (West Indies) are the other three teams in the field. None of the IPL teams who competed in 2009 could make an impression and the three teams playing in 2010 would seek to make amends for the previous edition's flop-show.

Leading the pack would be Mahendra Singh Dhoni’s Chennai, which has a formidable line-up of big-hitters such as Matthew Hayden, Mike Hussey, Suresh Raina, Albie Morkel and Justin Kemp.

Their bowling line-up features leading Test off-spinner Muttiah Muralitharan and they will be favourites to advance to the semifinals from Group A, which also features the Warriors, Victoria, Wayamba and Central Stags.

Royal Challengers Bangalore, who were there in the field even the last time around, have a stronger batting line-up to boast of with the ever-reliable Rahul Dravid, explosive New Zealander Ross Taylor and the versatile South African Jacques Kallis.

The bowling has inspirational skipper Anil Kumble leading the spin department with Dale Steyn adding zing to the pace attack. Kallis normally plays for the Warriors, while Taylor pads up for the Central Stags but both the players were bought by the IPL franchise after paying a $200,000 compensation to their respective state teams.

"The biggest challenge is how quickly you acclimatise to the conditions and the need to start well in the tournament," said Kumble. Sachin Tendulkar's Mumbai, on the other hand, also have a formidable look with their batting having the firepower of South African big-hitter JP Duminy and West Indian sensation Kieron Pollard.

The bowling features Zaheer Khan and Harbhajan Singh with Sri Lanka pacer Lasith Malinga proving the support. "We have champions from all cricketing nations, so it's as tough as it can get. It is competitive ... And we have world-class players participating," said Tendulkar.

Mumbai grouped with Bangalore, the Highveld Lions, South Australia and Guyana. The team they face in the tournament-opener on Friday, Highveld Lions, can be tagged as the underdogs. Banking on local support and some fireworks from batsmen such as Alviro Petersen and Neil McKenzie to match up to Mumbai's might.

The tournament would be played out in Johannesburg, Pretoria, Durban and Port Elizabeth, with the final on September 26.