This was Pujara's second successive century in ongoing one-day tournament.
After being asked to bat first as Surrey captain Ben Geddes won the toss, Sussex lost openers Ali Orr and Harrison Ward for single-digit scores.
Then Tom Clark (104 with 13 fours) and Pujara added 205 runs for the third wicket, while Pujara continued to pillage the Surrey bowlers. Pujara has last scored 107 in just 79 balls against Warwickshire and continued his good form here as well.
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He reached the 100-run mark in 103 balls and finally well for 174 runs in 131 balls with 20 fours and 5 sixes. This is also his List-A best score, beating his previous best of 158*. Interestingly, his final 74 runs came off just 28 balls and he helped Sussex put 378/6 in 50 overs at the Hove County Ground.
For Surrey, Conor McKerr picked two wickets while Tom Lawes, Matt Dunn, Amar Virdi and Yousef Majid claimed a wicket each.