A goal from teenager Jordan Ball on his senior debut was enough to give Doncaster a 1-0 win and knock Johnstone's Paint Trophy holders Chesterfield out of the competition.
Ball's first act after being introduced as a substitute after 83 minutes was to head home David Cotterill's deep corner and book his side's place in the next round.
Coventry progressed through after a 4-0 second-half rout at York.
Goals from David McGoldrick and Callum Ball, an own-goal from Jamal Fyfield and a further strike from Chris Hussey wrapped up the win.
Preston substitute Akpo Sodje scored twice to earn his side victory a 4-2 win at Morecambe.
Crewe eased through to the third round after a slick display secured a 2-1 win at Shrewsbury.
Luke Murphy and Max Clayton put The Alex 2-0 up before substitute Asa Hall pulled one back.
Bury went through after a a 5-4 penalty shoot-out win at Spotland against arch-rivals Rochdale.
Bradford reached the third round 3-2 on penalties after a goalless draw at Hartlepool.
Port Vale won a dramatic penalty shoot-out 6-5 to knock Walsall out after the two teams drew 2-2 in normal time at the Banks's Stadium.