Danushka Gunathilaka, Sri Lanka, MS Dhoni, India, ICC Champions Trophy 2017
Danushka Gunathilaka gets ready to play a reverse-sweep, June 8, 2017Ian Kington/AFP/Getty Images

Group B was supposed to be pretty cut and dry – two teams at the top of the tree in the ICC rankings, and two teams near the bottom, in transition, struggling to find their identity.

When India thumped Pakistan and South Africa eased past Sri Lanka, that cut and dry feeling only got stronger – here was a group that was only going one way, with India and South Africa qualifying for the semifinals.

Two more matches later, though, all that has been flipped right around.

Pakistan put on a masterful bowling performance to topple South Africa and then, on Thursday, with almost the entire crowd against them, Sri Lanka batted in a manner that would have made Mahela Jayawardene and Kumar Sangakkara proud, mowing down a massive total against India.

ICC Champions Trophy 2017 standings

Now, with one game to go for each team, everybody is equal on points, and it is anybody's guess on which two teams are going to go through to the semifinals.

Just like that, a mundane-looking, predictable group has turned into the most exciting one in the ICC Champions Trophy 2017.

It was all thanks to some glorious batting from Sri Lanka, led by two youngsters, who put on a beautiful partnership – one a left-hander and the other a right-hander. Yup, it was almost as if Mahela and Sanga were batting together again, tormenting the Indian bowlers.

Kusal Mendis, Sri Lanka, India, CT 2017, Group B
Kusal Mendis admires a beautiful shot of his that flies to the boundary, June 8, 2017Ian Kington/AFP/Getty Images

And this was no ordinary India bowling lineup. This was one that had bowled New Zealand and Bangladesh out in warm-up games and then ripped through Pakistan quite easily. This was a bowling lineup that looked potent with the new ball, effective in the middle overs and deadly at the death, if needed.

Sri Lanka made this India bowling lineup look ordinary, even if they were helped by the flattest pitch in the ICC Champions Trophy yet.

Oh, how India would have liked a drier pitch, one that would have brought Ravindra Jadeja into play a little bit more and made those changes of pace from the seamers more effective.

However, what they got at The Oval was a pitch that stayed true for the 100 overs – well, 98.4 overs – and allowed Danushka Gunathilaka (76, 72b, 7x4, 2x6) and Kusal Mendis (89, 93b, 11x4, 1x6) to put on a marvellous partnership that left the India bowlers with no answer.

After the dangerous Niroshan Dickwella fell early, and chasing India's score of 321, pressure was pretty high on these two batsmen, who have played less than 50 matches put together.

However, Gunathilaka, only in the Sri Lanka squad, let alone the playing XI, after Chamara Kapugedera got injured, and Mendis stayed calm, played some glorious cricketing shots, targeted Jadeja, rode their luck a touch and went on to add 159 runs in 23.1 overs for the second wicket, 159 runs that broke India's back.

India did their best to come back into the game, inflicting two brilliant run outs, that left the two batsmen back in the dressing room, but by then the damage was already done, and Angelo Mathews, Kusal Perera and Asela Gunaratne made sure this Group B would go right down to the wire.