AS Rangers prepare to welcome Lyon to Ibrox on Thursday night in their Europa League group stage opener there are concerns about the availability of some key central defenders.

Connor Goldson missed Saturday’s victory against St Johnstone after self-isolating, a big loss given his leadership qualities and ability to find deadly long passes from the back.

While Rangers managed without him in a 2-1 win, fellow defender Filip Helander was stretchered off with Steven Gerrard sounding pessimistic about the nature of the injury and admitting it “doesn’t look good”.

He will miss the match and potentially many more which leaves Steven Gerrard a little short for cover given his Europa League squad picks.

Here The Rangers Review analyses what defensive options are available.

Leon Balogun

The Nigerian filled in for Goldson at McDiarmid Park and will be certain to retain his place at the heart of the defence given the injury sustained by Helander.

He was preferred over the Swede for five of the six group matches last season so it’s clear Gerrard is a fan of pitching him in in these crucial European fixtures.

Very mobile and quick for a man of his stature, he's been a crucial squad player since arriving from Wigan on a free transfer and in a testing continental environment, his qualities will be important to get the three points.

Connor Goldson

The vice captain’s omission on Saturday was the first match he has sat out since the 2-0 Scottish Cup victory over Stranraer back in January 2020.

On Goldson, Steven Gerrard said afterwards: "He is self-isolating. Time will tell (how big a blow it is).

"He has been an important player for us. He has been very crucial since day one for me.

"We would love to have him available."

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Given the self-isolation rules, his return against Lyon will depend on when Goldson initially went into quarantine and if he has been double vaccinated.

The existing Scottish Government rules state that anyone who has been in close contact with a person who has tested positive must self-isolate for ten days. But if Goldson is fully vaccinated, asymptomatic and returns a negative PCR test result, it would enable him to end his self-isolation period early.

It’s still unclear if he has any Covid symptoms but given Gerrard’s comments, there appears to be optimism the big defender will be back available for selection.

A leader at the back and a brilliant long-passer out of defence, his return would be a huge boost to Rangers' chances.

Calvin Bassey

Preferred over Borna Barisic at left-back on Saturday, flexible Bassey can also play in the centre. The 21-year-old was utilised as a centre half in last season’s 4-0 thumping of Falkirk in the League Cup and has played in that position numerous times when coming through the youth ranks at Leicester City.  While playing that role in a Europa League tie is a completely different ball game, the powerful youngster isn't the type to be outfought or overawed by the big occasion. He has performed brilliantly so far this season and provides solid good cover if it's needed.

Leon King

The talented 17-year-old is another option available to Steven Gerrard. He’s included in the European squad due to the homegrown player rules.

It stipulates that 25-man European squads must contain eight homegrown stars. That is players who’ve been trained in Scotland for at least three years before the age of 21 – with four of those homegrown at each club.

The ruling saw King being included as part of the matchday squad for five matches in the Europa League last season although he didn't see any game time.

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It would be a baptism of fire should Gerrard put his trust in the teenager and evoke memories of Danny Wilson making his European debut at the same age away to Unirea in the Champions League in 2011. The then-youngster was outstanding that night but did have the colossus that was Davie Weir talking him through the game.

Still, the use of such an untested player seems like an unlikely scenario given the other options still at Gerrard's disposal.

Jack Simpson

Despite replacing the injured Helander at McDiarmid Park on Saturday, Simpson is unavailable against Lyon due to the fact he’s not included in the 25-man European squad.

He's also ineligible to be selected as part of the alternate B squad that teams are allowed.

Clubs are permitted by UEFA to submit an A list of players (List A) and a B list of players (List B).

List A is the first team squad submitted by Rangers on September 2nd while each club is entitled to register an unlimited number of players on List B during the season.

That list has to be submitted by midnight on the day before the match in question.

UEFA's regulation 45.11 on List B eligibility states: "A player may be registered on List B if he is born on or after 1 January 2000 and has been eligible to play for the club concerned for any uninterrupted period of two years since his 15th birthday by the time he is registered with UEFA, or a total of three consecutive years with a maximum of one loan period to a club from the same association for a period not longer than one year. Players aged 16 may be registered on List B if they have been registered with the participating club for the previous two years without interruption."

Simpson would therefore not qualify to be included on List B which leaves him ruled out of what is a huge clash on Thursday night.