India take on a beleaguered Sri Lanka in the dead rubber on Friday at hoping its off-colour batsmen will find form.

With Wednesday's 46-run victory fetching India an unassailable 3-1 lead in the five-match series - ensuring their first-ever bilateral ODI series triumph against Sri Lanka - the team is upbeat, hoping to sign off in style.

The lone worry stems from the poor form of Gautam Gambhir, Yuvraj Singh and Rohit Sharma and the team hopes they too would join the party on Friday.

Though an inconsequential match allows the think-tank to tinker with the team combination, the off-colour players are expected to figure in the playing XI in an effort to help them wriggle out of their bad patch.

There, however, is no such worry with the bowlers who did an excellent job in the series. Zaheer Khan, Munaf Patel and Harbhajan Singh once again rose to the occasion on Wednesday and helped in containing the hosts with their intelligent bowling.

Another redeeming feature of the fourth ODI was the smart fielding by the Indians after messing it up in the previous matches.

Experts in Colombo feel the toss was also in important aspect of the strategy and that the visitors benefitted out of it.

"The Sri Lankans also have a good batting line up. They could have scored more runs but for playing under the lights," an official remarked after Wednesday's match.

In fact, Indian skipper MS Dhoni himself admitted that the toss played a crucial role in the win as it assisted the spinners in the later part of the game.

"It was a good toss to win, there was something in the wicket for the spinners and they got a lot of turn. Even the pacers did well," Dhoni said.

India could last night make up for an additional batsmen as Yuvraj played a pivotal role as the second spinner, getting two important wickets.

Sri Lankan skipper Mahela Jayawardene said the spinners were getting more turn in the end of the innings. Though only three Indian batsmen - Suresh Raina, Virat Kohli and Dhoni - came up with worthwhile contributions, the vital partnerships kept the Indians going.

"The toss proved crucial, it put the Indians in an advantageous position but I should say we made too many mistake along the way. There was lack of consistent partnership from the batters and that did not help the team at all," Jayawardene rued.

The Sri Lankan skipper is also concerned about the opening combination. Replacing out-of-form Kumar Sangakkara with Malinda Warnapura at the top proved futile as the 29-year-old left-hander could not even open his account after facing 18 deliveries.

Friday's game could still be a cliffhanger as Sri Lankans were not very short of the Indian total during the last two match, losing by 33 and 46 runs respectively.

They only need a few of their star batsmen to click before they turn the corner and bridge the deficit 3-2.