The Virat Kohli-led Indian team will face a do-or-die situation when they take on West Indies in the second ODI of the three-match rubber here on Wednesday as the visitors lead the series 1-0 after hammering the Men in Blue by 8 wickets in Chennai.

Ahead of the clash, India pacer Deepak Chahar admitted that a below-par performance in the bowling and fielding department costed India the match.

Despite posting 287/8 on a slow track in Chennai, India failed to defend the total as Shimron Hetmyer and Shai Hope slammed respective hundreds to guide Windies to a comfortable win with 13 balls to spare.

Speaking on the eve of the second ODI, Chahar said: "To be honest, we didn't bowl well in the 1st ODI. Hopefully, if we are in a similar situation in the 2nd ODI, we will have to bowl better as a unit.

Fielding has been lacking in the last 4 matches. We have dropped too many matches. If we drop catches, against these big hitters who try to hit more sixes than boundaries, then it will become very difficult for us. As a fielding unit and bowling unit, we need to improve," he added.

Chahar also revealed he finds ODI cricket a lot tougher than the T20Is and Tests but is trying to improve his ability to bowl in the slog overs, which he feels will make him more effective in the 50-over format.

"I think ODI is the toughest format. In T20Is, you know what to do. Even if you give away 24 runs but don't pick up a wicket, that is still good bowling. In Tests, you have to keep attacking, even if you give away runs but pick up wickets, it's good for the team," Chahar pointed.

"However, in ODIs, you have to mix both -- pick up wickets and contain the runs as well. You have to read the situation really well. You need to understand what the team wants from you.

You need to assess the batsman and then decide whether to contain or get him out. ODI is more difficult than both formats. I have played a lot of One-Day cricket with India 'A' which has helped me.

"In the past, I struggled to bowl in the middle overs. In the powerplay, it's about containing runs, in death, you have to stop batsman going after you. But in the middle overs, I have gotten better. I am learning. I will learn as I progress," the pacer said.

Meanwhile, Chahar said he is working on improving his pace and on getting the ball to move at pace. "When I played Ranji Trophy for the first year, I used to bowl at around 125 kph. I struggled with injuries because I wanted to improve my pace. I knew I wouldn't survive in international cricket with that pace. I had to bowl close to 140 kph.

I always wanted to bowl close to 140 kph and swing the ball at that pace. It becomes deadly then. I think playing a bowler bowling at 140 kph and swinging the ball is more difficult than playing someone who bowls at 150 kph," Chahar said.

As India have a busy schedule for the next few months, Chahar said he will focus to avoid injuries in order to keep himself fit for national duty. "In the next 6 months, there's a lot of cricket to be played. My main focus is to keep myself fit. I want to play all the matches. I want to avoid the injuries that have occurred to me in the past," he said.