Joe Pigott scored twice as Luton stunned second-placed Oxford United with a 3-2 win at the Kassam Stadium to boost their faint hopes of reaching the Sky Bet League Two play-offs.Danny Hylton got the U's off to the perfect start with his 14th goal of the season after two minutes, from Kemar Roofe's pass - Hylton's low right-footed shot having too much power for Luton goalkeeper Elliot Justham.Pelly Ruddock Mpanzu scuffed a shot wide from 15 yards as the Hatters tried to hit back.Yet the home side did not look in much danger until a calamitous goalkeeping error on 44 minutes from Benji Buchel, who slipped, allowing Josh McQuoid to square for Piggott to tap into an empty goal.Then, two minutes into first-half stoppage time, Johnny Mullins' panicky clearance gave Danny Green the opportunity to cross from the right, and Olly Lee smashed it home with a stunning volley.Oxford, shellshocked at half-time, were back level on 51 minutes when centre-half Chey Dunkley headed in Chris Maguire's free-kick.But Piggott fired Luton back in front on 58 minutes with a tidy finish from the left side of the box.Sub James Roberts almost snatched an equaliser late on, with Justham superbly pushing his shot against a post to dent Oxford's automatic promotion hopes.