Compton's debut means new landmark.
Both will be hoping to be involved when the U's take on Doncaster Rovers at the Keepmoat Stadium this weekend.
He was quickly followed by the 601st, when George Porter also made his debut in the match at the Broadfield Stadium.
Having penned a deal to join the U's from Portsmouth, Jack's second half introduction in the defeat to Crawley saw him take the U's into the 600s since their arrival in the Football League in 1950.
Jack Compton's debut against Crawley Town saw him become the 600th player to represent Colchester United in the Football League.