Match ends, Brentford 0, Oxford United 4.
League Two side Oxford United thrashed Championship outfit Brentford to reach round two of the Capital One Cup.
Liam Sercombe struck from 18 yards to put the U's ahead, before home keeper Jack Bonham's clearance cannoned off Danny Hylton and flew into the net.
Kemar Roofe made it 3-0 with a superb 40-yard lob after collecting Bonham's headed clearance on 12 minutes.
John Mullins fired in the fourth after the break as the Bees, who gave debuts to eight players, were well beaten.
Oxford, who lost on penalties to Premier League side West Brom in the second round last season, had failed to win in their previous seven visits to Griffin Park.
However, they had victory all but secured within 15 minutes against a Brentford team showing 11 changes from Saturday.
The U's, tipped to push for promotion to League One this season, took the lead on five minutes before Hylton's fortuitous strike made it 2-0 after nine.
Roofe's fantastic effort ended the match as a contest before Mullins slotted a fourth after the break.
The League Two side are marking the 30th anniversary of their sole major trophy win, the League Cup final in 1986, this season.
Brentford manager Marinus Dijkhuizen: "It was an embarrassing performance from my team. After 12 minutes it was 3-0 and game over.
"There were a lot of lessons tonight for me and for the players. That's a good thing. The bad thing is we played awful.
"You have a lot of changes and maybe too much. And I was surprised that there was no leadership in the team tonight."
Oxford boss Michael Appleton: "We were all frustrated after Saturday [a 1-1 draw with Crawley] and I asked for a quick start.
"We looked at the video from the Ipswich game and they pressed them really hard to get their rewards. I am absolutely delighted for them.
"[Roofe's goal] was a fantastic finish - a goal in a million. I am sure it will be all over the TV and be one of the contenders for goal of the season already."
- 5BjellandSubstituted forBidwellat 45'minutes
- 28YennarisSubstituted forMcCormackat 53'minutes
- 37SeniorSubstituted forGogiaat 75'minutes
- 4RoofeSubstituted forO'Dowdaat 45'minutes
- 8SercombeBooked at 65mins
- 11MacDonaldBooked at 31minsSubstituted forRuffelsat 59'minutes
- 20TaylorSubstituted forHobanat 65'minutes
- Dean Whitestone
- Shots on Target
Second Half ends, Brentford 0, Oxford United 4.
Attempt saved. John Mullins (Oxford United) right footed shot from the centre of the box is saved in the centre of the goal.
Attempt blocked. Danny Rose (Oxford United) left footed shot from outside the box is blocked.
Corner, Oxford United. Conceded by Jack O'Connell.
Attempt missed. Callum O'Dowda (Oxford United) right footed shot from outside the box misses to the right following a corner.
Corner, Oxford United. Conceded by Jake Bidwell.
Corner, Oxford United. Conceded by Yoann Barbet.
Attempt missed. Ryan Williams (Brentford) right footed shot from outside the box is just a bit too high from a direct free kick.
Alan McCormack (Brentford) wins a free kick in the attacking half.
Foul by Liam Sercombe (Oxford United).
Jack O'Connell (Brentford) wins a free kick in the attacking half.
Foul by Pat Hoban (Oxford United).
Foul by Josh Clarke (Brentford).
Callum O'Dowda (Oxford United) wins a free kick in the defensive half.
Foul by Jake Bidwell (Brentford).
Danny Hylton (Oxford United) wins a free kick on the left wing.
Jake Bidwell (Brentford) wins a free kick on the left wing.
Foul by Danny Hylton (Oxford United).
Delay over. They are ready to continue.