Derby have spent most of this half on the front foot but they do have a goal to show for their efforts.
Eiran Cashin's header off the bar is the closest they have come.
Reading would probably take a point to move a little bit further away from the bottom four.
Portsmouth 1-0 Burton
Image source, Getty ImagesKusini Yengi's injury-time penalty has Portsmouth in front at half-time.
His glaring miss and Panenka spot-kick will be the talking points amongst the Pompey faithful as the team are 45 minutes away from racking up another win.
HT: Grimsby 1-0 MK Dons
Toby Lock
MK Citizen's sports editor on BBC Three Counties Radio
A poor half from MK Dons. They need get something in that final third because so far nothing's stuck.
Michael Kelly has kept them in it, even though he gave away the penalty. It was a rubbish penalty from Grimsby - straight at the goalkeeper.
Image source, Rex FeaturesBottom side Carlisle had taken a shock early lead over play-off hopefuls Barnsley through Luke Armstrong but Jordan Williams has brought the Tykes level.
After the very early opener Jack Moylan (above) has scored a second for Lincoln against Cambridge. Can the Imps push their way into the top six?
The Us are without a win in five games but do have a five point cushion above the bottom four.
And the mid-table battle at the New Meadow is going firmly in favour of Exeter with Jordan Shipley sent off in just the sixth minute for Shrewsbury before Will Aimson and Luke Harris scored for City.
Tranmere 1-1 Mansfield
A good advert for League Two, this.
Regan Hendry arrowed into the corner from the left of the area to put Rovers ahead but they couldn't add to their lead and Will Swan's sublime touch and dinked finish has put the leaders back on at Prenton Park.
All to play for in the second 45.
Kusini Yengi (45+3 mins pen)
That takes some nerve!
He has missed an absolute sitter, but Kusini Yengi decides to go with the Panenka penalty and he succeeds!
Max Crocombe had dived out of the way as the ball softly ends up in the middle of the net.
Grimsby 1-0 MK Dons
This wasn't in the script... Justin Obikwu's second goal in three days has given the struggling Mariners a precious half-time advantage against in-form MK Dons, who are looking to move into the automatic promotion places tonight, .
Drama seconds before the whistle, however, as Gavan Holahan saw a penalty kick saved by MK keeper Michael Kelly, who had brought down Obikwu to give away the spot-kick.
Will the hosts be made to pay?
Portsmouth 0-0 Burton
Kusini Yengi receives the ball in the box, wriggles his man and is brought down.
Penalty!
Bolton 2-0 Oxford
Image source, Rex FeaturesOxford need a win tonight to leapfrog Stevenage into the top six.
Only the three goals required to do that now!
Josh Dacres-Cogley (27 mins)
Image source, Rex FeaturesA birthday gift for Josh Dacres-Cogley!
A long punt forward should be dealt with by Oxford, but it's a complete mix-up between defender Greg Lee and goalkeeper Jamie Cumming.
The ball ricochets between them, allowing Dacres-Cogley, 28 today, the chance to lift the ball into the unguarded net.
It's not been a good night for several sides chasing the play-offs so far.
Morecambe, who started this evening just a point outside the top seven, trail 2-1 at Newport having conceded goals to Aaron Wildig and Adam Lewis within 18 minutes before Gwion Edwards got a goal back.
Omar Bugiel has put Wimbledon in front at home to Gillingham, who started the night outside the play-offs only on goal difference.
And Crawley trail at home to Sam Austin's goal for Notts County, with the Magpies having lost four games on the spin.
Portsmouth 0-0 Burton
Oh my word, Portsmouth should be ahead!
Look away now, Kusini Yengi, as the young Aussie has missed an absolute sitter. Paddy Lane provides the but Yengi misses an open goal from no more than three yards!
Bolton 1-0 Oxford
Jerome Sale
BBC Radio Oxford commentator
Bolton are a good side but they are a League One side. Oxford might be able to lull them into a false sense of security because they are also a good side - albeit also a League One side.
Derby 0-0 Reading
Desperately close to a Derby opener.
Conor Hourihane swings in the free-kick which is met by the diving head of Eiran Cashin, but it comes back off the bar from the Irish centre-half.
Will Swan (39 mins)
It's been coming... Will Swan will feel a lot better after missing the target with a free header when the game was still 0-0.
He's taken Louis Reed's ball over the top under his spell with a gorgeous touch and lifted the ball over the sliding Luke McGee and into the back of the net from an angle.
The leaders are level.
Tranmere 1-0 Mansfield
The visitors are doing their best to get into this one and George Maris has been denied by a superb block after he fired in a shot which looked destined for the back of the net from Aaron Lewis' cross.
Portsmouth 0-0 Burton
Image source, Getty ImagesOver half an hour gone on the south coast and Portsmouth yet to find the breakthrough.
A sign of how it's going though, is that Burton goalkeeper Max Crocombe has been shown a yellow card for timewasting.
Justin Obikwu (33 mins)
Now then... this is a big goal. MK Dons are trying to move into the automatic promotion places but they trail at Grimsby who are fighting for their lives.
Justin Obikwu is the man to get it, turning home a cut-back from Mo Eisa past Michael Kelly. He got a crucial leveller at Sutton on Saturday, his first for the club, his second might just be even bigger.
Grimsby 0-0 MK Dons
Gary Croft
Former Grimsby defender on BBC Radio Humberside
MK Dons look like a good side; especially the middle two that are making things click. The wide men are rotating in too and it's difficult for Grimsby Town to try something.
Town have been organised though - they've kept their shape.
Nathanael Ogbeta (19 mins)
Image source, Rex FeaturesExcellent Bolton goal.
They work the ball across the deck from right to left through Jon Dadi Bodvarsson to George Thomason and into Nathanael Ogbeta.
Playing as a left wing-back, he takes one touch to control before thumping it past Jamie Cumming in the Oxford goal.