Krishnakumar Dinesh Karthik is an Indian professional cricketer and commentator who plays for the India national cricket team and is currently in the Indian Premier League playing for the Royal Challengers Bangalore. He is also the current captain of the Tamil Nadu Cricket Team in domestic cricket. He made his debut for the Indian cricket team in 2004. Karthik has become the 4th Indian batsman to play 300 T20 matches. Karthik was a member of the team that won both the inaugural 2007 T20 World Cup and the 2013 ICC Champions Trophy.

Karthik's cricketing journey began at the age of 10, with his father as his first coach. He played in Tamil Nadu's youth teams and made his Under-14s debut in 1999. A year later, he was promoted to the Under-19s and made his first-class debut in the 2002-03 season. His performances in the Ranji Trophy earned him a place in the Indian squad for the 2004 Under-19 Cricket World Cup in Bangladesh.

In 2004, Karthik made his international debut for India against Australia, but his stint was short-lived due to his poor performance. He was recalled to the Indian side in 2007 for a tour of Bangladesh and made a comeback in 2008 for a tour of New Zealand, but his middling performances did not allow him to cement a place in the team.

Karthik's international career was marked by inconsistency, with him being in and out of the Indian team. However, he continued to perform well in domestic cricket, scoring over 1000 first-class runs in the 2008-09 season and maintaining a batting average above 40 for five consecutive seasons. In 2014, Karthik was recalled to the Indian team for a tour of Bangladesh.

Karthik's role in the Indian team has changed over the years, from a wicketkeeper-batsman to a specialist batsman. He has been recalled to the Indian side multiple times, showcasing his batting prowess and adaptability on challenging pitches.

Karthik's contributions to the Indian Premier League (IPL) cannot be ignored. He has been a sought-after player in the lucrative tournament and has attracted heavy bids from various franchises. In 2014, he was purchased by the Delhi Daredevils for a staggering INR 12.5 crore, making him one of the highest-paid players in the competition. The following year, he was snapped up by the Royal Challengers Bangalore for INR 10.5 crore. In 2016, he joined the Gujarat Lions for INR 2.3 crore.

In 2018, Karthik took over as the captain of Kolkata Knight Riders and led the team to the final of the Indian T20 League. His performance in the final, where he scored 29 runs off 8 balls, including a last-ball six, earned him the reputation of being a reliable finisher.