Pat Fenlon’s side hadn’t won at Dalymount since beating Drogheda United back in March. That was Fagan’s last start in Phibsboro and he once again showed excellent touch and awareness, capping his display by winning and then scoring his side’s match-winning penalty.
With Glen Cronin and Ger O’Brien also back, Fenlon could field arguably his strongest team this season.
But it was UCD, win a gusting wind at their backs, who might have found themselves ahead after just three minutes. Bohemians keeper Chris O’Connor’s loose clearance fell to Dean Marshall who just never got hold of his attempted chip, which was easily cleared.
There was another let-off for Bohs on 19 minutes when Paul O’Conor chipped wide with only O’Connor to beat.
Barron then excelled in the opposite goal when he saved from Robert Bayly.
He could do nothing on 25 minutes, however, when Fagan confidently fired home from the spot after UCD skipper Michael Leahy had handled inside the area.
UCD remained a threat and should have been level at half time as Darren Meenan narrowly missed the target with two efforts.
Bohs’ Killian Brennan rattled the bar with a free-kick six minutes into the second period before firing another dead-ball just wide three minutes later. A third free-kick required Barron to push it around the post.
A tired Fagan would have a final cameo before being taken off on 78 minutes when controlling Brennan’s pass on his chest, turning adroitly and firing just wide.
O’Brien might then have added a second in the final minute, shooting just wide after a terrific run from the left-back position.
BOHEMIANS: O’Connor; Heary, Burns, Price, O’Brien; Buckley (Dixon 81), Cronin (Burke 86), Bayly, Brennan; Flood, Fagan (Traynor 78).
UCD: Barron; Harding, O’Connor, Leahy, Nangle; Marshall, O’Conor, Corry (Ledwith 46), Meenan; Benson (Rusk 51); Belhout (Doyle 68).
Referee: Neil Doyle (Dublin).