Prithvi Shaw became the youngest Indian to score a Test century on debut as India rode on the Mumbai teenager's fluent 134 to post 232/3 at Tea against the West Indies in the first Test here on Thursday.Shaw, at 18 years and 329 days, reached the historic three-figure mark off just 99 balls at the Saurashtra Cricket Association Stadium.Shaw is also the second youngest Indian ever to score a Test century after Sachin Tendulkar who cracked a ton at 17 years and 107 days in 1990 vs England in Manchester.Shaw, who opened the innings for India, took 99 balls to get to his maiden hundred. His innings was laced with 15 boundaries.Besides Shaw, Cheteshwar Pujara also scored a good looking 86 in his own backyard but missed out on a hundred.Skipper Virat Kohli, who was all smiles when young Shaw raised his bat after reaching the milestone, was at the crease on 4 with vice-captain Ajinkya Rahane (batting 0) with Shaw offering an easy return catch to leggie Devendra Bishoo trying to play against the turn.Shaw and Pujara added 206 runs for the second wicket as the tourists were sent on a leatherhunt for large parts of the second session.Shaw's innings was studded with 19 fours while Pujara hit 14 boundaries before poking at a length ball half-heartedly to wicketkeeper Shane Dowrich off pacer Sherman Lewis, who bagged his first Test scalp.Earlier, Opting to bat, the hosts lost K.L. Rahul for a duck in the very first over of the two-match series as Caribbean pacer Shannon Gabriel caught the Indian opener in front of the wickets.Brief scores: India 232/3 in 51 overs (Prithvi Shaw 134, Cheteshwar Pujara 86, Virat Kohli batting 4, Ajinkya Rahane batting 0; Shannon Gabriel 1/38)