Kirk Millar misses a glorious chance to put Linfield back in front almost immediately but can't get a strong enough purchase on his effort as Henri Perk makes a routine save.

CSKA Sofia go close to extending their lead as Jean-Phillipe Gbamin launches an audacious effort from inside his own half which beats Brian Maher but sails narrowly wide of the Derry City goal.

Linfield concede a penalty and Ethan McGee is sent off for handling the ball inside his own box.

Derry City should be back in front again as Dimitar Emitov parries Brandon Fleming's flick on. The loose ball hits a defender but the keeper somehow reacts to save on the line.

Rommi Siht pounces on lackadaisical defending from Linfield and forces Chris Johns into a save from distance.

The Linfield keeper makes a fairly comfortable save and gathers at the second attempt to thwart the danger.

Linfield striker Matthew Fitzpatrick is booked for a foul on a Kalju defender.

Double change for the CSKA Sofia as Joel Zwarts and James Eto'o replace Leandro Godoy and and Petko Panayotov.

We are back under way again after a stoppage of more than 10 minutes.

Hopefully we can concentrate on the football for the rest of the game.

Kalju goalkeeper Henri Perk makes a super stop down to his left at full stretch to deny Darragh Leahy from opening the scoring on the volley.

Calm seems to have been restored as the Derry City fans who had to come onto the pitch have now returned to their seats.

We are now awaiting the return of both teams.

Linfield have started the game firmly on the front foot and find themselves camped inside the Kalju half.

That being said, it's the visitors who have the first sight of goal as Danyl Mashchenko strikes from outside the area and forces Chris Johns to make a save.

The Estonian side look threatening on the counter attack.

We have a stoppage in play here as referee Jasmin Sabotic takes the players off the pitch after the away fans try to break through the cordon dividing them from the Derry City support.

There are a number of home fans on the pitch as they try to get away from the disturbance.

We're under way at Windsor Park.

Can Linfield turn this tie on it's head and book a European renewal with Shelbourne in the second qualifying round of the Conference League, or will David Healy's side fall short against Nomme Kalju?

Derry City should be in front in the tie as Barry Cotter picks out Ellis Chapman in front of goal, but the midfielder on the stretch puts the ball wide from close range.

The hosts are well on top at the minute.

Linfield manager David Healy said reports linking him to the Shelbourne job was "people putting two and two together and coming up with any number they want".

Shelbourne announced on Monday that Sligo Rovers manager John Russell has signed a long-term contract to become their new head coach.

That news followed reports that Healy, who has been at the helm at the Blues since 2015, had reportedly held talks with the League of Ireland club, something which he refuted.

"I've huge respect for Shelbourne as a football club, I've been down to Shelbourne with Ross [Oliver, assistant manager] and Willie [McKeown, head of recruitment] a few weeks ago in preparation of us getting through this round [of the Conference League] and it was important to see them. That's what it was," he told BBC Sport NI.

"When you go down you sit with associates and club members, scouts and agents, but it doesn't mean you're sitting chatting about other things.

"There wasn't any communication club to club, it was people putting two and two together and coming up with any number they want."

Image source, Pacemaker Press

Linfield manager David Healy's thoughts ahead of tonight's game:

"Looking at last week, probably still tinged with a little bit of disappointment and frustration because I thought we were good value for at least a draw in the game.

"We had good opportunities which we passed up and in European games they're crucial.

"There's still the belief in how we can play and make Windsor hard for them."

Image source, Pacemaker Press