Sachin made his first-class debut for Kerala on 3 November 2009 in the 2009-10 Ranji Trophy. He made his List A debut for Kerala on 13 February 2011 in the 2010-11 Vijay Hazare Trophy. He made his Twenty20 debut for Kerala on 16 October 2011 in the 2011-12 Syed Mushtaq Ali Trophy.

Sachin scored heavily in the 2012–13 Vijay Hazare Trophy hitting 298 runs from seven matches with an average of 74.50. He scored his maiden List A century in the quarter-finals of the tournament, securing a place for Kerala in the final four. He represented South Zone in the 2012-13 Deodhar Trophy.

In August 2013, Sachin was named to the India A squad to play three unofficial ODIs against New Zealand A team.

Sachin was named Kerala's captain in the 2014-15 Ranji Trophy and made his maiden first-class century with an unbeaten 200 in the season. He scored a career-best score of 250 in the 2016-17 Ranji Trophy in the match against Services and was declared the man of the match.

Sachin was the captain of the Kerala team which qualified to play the quarter-finals of Ranji Trophy for the first time in the 2017-18 season. This was followed by the team's historical entry to the semi-finals of the tournament in the next season, again under his leadership.

Sachin's partnership of 338 runs with Sanju Samson in the match against Goa in the 2019-20 Vijay Hazare Trophy is the highest partnership in List-A cricket for Indian cricket and third highest in the format.