RYAN Clarke saved two penalties as Oxford United beat Plymouth Argyle in a shootout to book a place in the Johnstone's Paint Trophy area semi finals.
Sean Rigg, Adam Chapman and Liam Davis all converted from 12 yards to send the U's through.
James Constable had set up the shootout by coming off the bench to equalise Alex MacDonald's opener.
The game could have gone either way in normal time, but Plymouth finished with ten men after Durell Berry was sent off.
In the shootout Clarke again showed his prowess at saving penalties by denying Jamie Lowry and Maxime Blanchard.
Chris Wilder made five changes from the side which began Saturday's 3-3 draw at Accrington Stanley.
Tyrone Marsh was handed his first start and played in a front three with Alfie Potter and Sean Rigg.
Damian Batt and Davis came into the back four, Chapman and Jake Forster-Caskey operated in midfield, while Peter Leven and Tony Capaldi were rested altogether.
Mark Molesley stood out for the home side early on with several incisive runs.
One slaloming effort beat several players and was only brought to an end by Jake Wright on the edge of the box. From the resulting free-kick MacDonald's effort deflected narrowly wide.
United had a great chance on 16 minutes, when a hopeful ball forward from Davis turned into a defence-splitting pass for Rigg.
The winger raced through on goal, but even though Rene Gilmartin slipped, the goalkeeper regrouped in time to block the shot.
United had a scare a minute later, when Berry cut in from the right flank and hit a shot which hit the inside of Clarke's left hand post and bounced clear.
The home side built on the momentum and opened the scoring on 20 minutes.
Batt conceded a free-kick wide on Argyle's left flank and from around 25 yards MacDonald audaciously curled his shot past Clarke and into the top corner.
The United goalkeeper may have been disappointed to concede the goal, but did well to keep the score 1-0 just before the half hour mark.
MacDonald slipped a ball into Paris Cowan-Hall, whose shot from ten yards was smartly blocked by the stopper.
United enjoyed a decent spell leading up to half time, pushing Argyle back and winning a succession of set pieces.
They struggled to prise apart the Pilgrims' defence, though, not helped by a lack of quality on the final ball.
United's one good opening for an equaliser late in the half saw Rigg cleverly set up Forster-Caskey, whose shot from 15 yards was straight at Gilmartin.
Argyle started the second half brightly.
Molesley and Cowan-Hall tried their luck with sweetly-struck shots from distance which only just flew off target.
Wilder waited just nine minutes to freshen his side up, bringing on Heslop and Constable for Marsh, who worked hard but struggled to make an impact, and Cox.
Both substitutes were involved in United's equaliser just after the hour.
Heslop hung up a high cross, which Gilmartin flapped at under pressure from Rigg, allowing Constable to loop a header over a defender on the line and into the net.
The striker quickly turned provider, crossing for Batt to blast a shot wide with the next attack.
The game was in the balance as the half wore on.
Molesley, on loan from Bournemouth, was the hosts' main threat and came close with two more low drives.
At the other end Rigg exchanged passes with Constable, but his shot from an acute angle flew wide.
Plymouth played the final six minutes with ten men, as Berry picked up a second booking for a foul on Rigg.
United could not make the numerical advantage pay in the closing stages, so the tie was settled on a penalty shootout.
As in the Capital One Cup victory against Bournemouth in August, United kept their cool from the spot and Clarke played his part to the full.