Wolverhampton Wanderers secure their passage back into the Championship, while Brentford will have to wait a little longer to join the celebrations.
Kevin McDonald struck the opener on the stroke of half time, before a red card for Chuks Aneke gave Wolves the impetus to build on their advantage after the restart.
Dave Edwards struck midway through the second half to double his team's lead and help propel Kenny Jackett's men back into England's second tier at the first time of asking.
Meanwhile, Brentford suffered a hiccup in their bid to edge closer to joining the West Midlands outfit after Mark Warburton's charges slumped to a 1-0 defeat to Swindon Town.
Louis Thompson's strike moments before the half-time whistle proved enough for the Robins, who faced ten men for much of the second half after Adam Forshaw was red-carded for two bookings.
The Bees now sit seven points ahead of third-placed Leyton Orient, who proved that they were up for the fight by thrashing Gillingham 5-1 at the Matchroom Stadium.
David Mooney and Dean Cox fired the O's into a comfortable 2-0 lead after just 10 minutes, before Kevin Lisbie and the Irishman sent the Londoners into a commanding four-goal half-time lead.
Chris Dagnall added a fifth, while Craig Fagan notched a late consolation as five-star Orient reached the 80-point mark.
Elsewhere, MK Dons slipped nine points behind Peterborough United, who occupy the final playoff position.
Kgosi Ntlhe's sixth-minute strike proved enough for Posh to down Coventry City and consolidate their place in the top six, while the Dons slumped to a 2-0 home defeat to Crawley Town as goals from Andrew Drury and Mike Jones sealed the win
At the other end of the division, Notts County recovered from a two-goal deficit to beat Port Vale 4-2 at Meadow Lane.
An own goal from Curtis Thompson and a Gavin Tomlin strike had Vale cruising on the 25-minute mark.
However, a brace from James Spencer before half time helped restore parity, before a double from Jamal Campbell-Ryce sent Shaun Derry's men on their way.
The victory brings the Magpies out of the relegation zone on goal difference alone ahead of the remaining four fixtures.
Results in full: Crewe 0-2 Wolves, Leyton Orient 5-1 Gillingham, MK Dons 0-2 Crawley Town, Notts County 4-2, Peterborough United 1-0 Coventry City, Preston 6-1 Carlisle United, Stevenage 2-3 Colchester United, Swindon 1-0 Brentford, Tranmere 2-1 Shrewsbury Town, Walsall 0-1 Bristol City