Derry City produced their best game of the season to see off Bohemians and in doing so secured European football for next season.
Kenny Shiels' side were magnificent throughout and in truth they should have won a far bigger margin after a dominant display.
Bohs went close in the early stages but Kurtis Byrne's close range effort on the slide was straight at Derry goalkeeper Gerard Doherty.
Derry didn't heed that warning as the visitors took the lead on 18 minutes as Byrne got in behind the home side's defence after Niclas Vemmelund has lost possession and rounded Doherty before slotting the ball home, despite Conor McDermott's best attempts to clear.
The woodwork came to Bohs' rescue just before the half-hour mark as Aaron McEneff's stinging 25 yard drive, which had Delany beaten, came back off the post.
Derry continued to attack a super pass by Keith Ward found Rory Patterson at the back post, but his volley was superbly tipped onto the side netting by a diving Delany.
Just after the half-hour mark a Keith Ward left wing corner found Vemmelund, but his header from close range flew just wide.
Derry rattled the woodwork for a second time just before the break as Patterson's stinging drive smashed back off the crossbar, after Delany's cut-back had created the chance.
Kenny Shiels' side deservedly levelled things on 50 minutes as McEneff scored his sixth penalty of the campaign, after referee Derek Tomney had adjudged that Derek Pender had brought down Dean Jarvis inside the box.
City took the lead on 64 minutes after the mother of all scrambles ended with Patterson netted his fifth goal in four games against Keith Long's side.
Delany made a remarkable save on 74 minutes he somehow kept out Ronan Curtis' close range header.
Right at the death Derek Prendergast should have stolen a point for Bohs but he headed wide from close range.
Derry City: Doherty, McDermott, Vemmelund, Castells (Karner 91), Jarvis; Daniels, McEneff (McCormack 76), Ward (Holden 76), Monaghan; Patterson, Curtis.
Bohemians: Delany, Pender (O'Halloran 61), Prendergast, Hayes, Fitzgerald; Kavanagh, Buckley, Hayes, Wearen (Quigley 79), Kelly (D Byrne 61); K Byrne.
Referee: Derek Tomney (Dublin).
