Why are McBurnie and Stewart not in World Cup mix?

Can Clarke change his options front? Does he even want to? And, if he does, is he even looking in the right places?

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Clarke has taken Scotland to two European Championships and they've scored three goals in six games in those tournaments, one of them an own goal against Germany and another from a Scott McTominay shot against Switzerland that found the net only after a huge deflection.

Only one Scottish player has scored directly in any of those group games - Callum McGregor against Croatia in Clarke's first Euros.

The concern, therefore, is that Clarke doesn't see fit to shake things up, to gamble a little. As a creature of habit, we could almost predict which way he's going to go on all of this.

He'll have five or six strikers/wingers in his squad - Che Adams, Lawrence Shankland, Lyndon Dykes, George Hirst, Tommy Conway and Ben Gannon-Doak. He knows them, he trusts them and it would be a huge surprise if he doesn't pick them.

The hope - forlorn, most likely - is that he still has an open mind on one or maybe two positions in that lot.

Comparing levels is not easy. How does a goal in the Scottish Premiership compare to a goal in the English Championship or Italy's Serie A? And how about the relative strength of the team it's scored for against the team it's scored against?

A Shankland goal against the Old Firm versus an Adams goal against Roma, currently sixth in the table. How do you weigh them up?

Crudely, if you constructed a league table of Clarke's options at centre-forward based on this season's tallies of goals scored, minutes-per-goal and goals-per-shots in club football then this is how it would read.

First - Ross Stewart of Southampton. Second - Oli McBurnie of Hull City. Third - Lawrence Shankland of Heart of Midlothian. Fourth - George Hirst of Ipswich Town. Fifth - Kieron Bowie of Hibernian and now Hellas Verona. Sixth - Che Adams of Torino. Seventh - Tommy Conway of Middlesbrough. Eighth - Lyndon Dykes of Birmingham City and now Charlton Athletic.

On Wednesday evening, Stewart scored for Southampton, currently fourth in the English Championship but only three points off an automatic promotion spot to the Premier League.

It was his sixth goal in 11 games and his ninth in 28 in a season that has been curtailed by injury. He missed 16 matches. Stewart has been desperately unlucky in that regard for three seasons, but he looks fit and well now.

The former Ross County and Sunderland player scored the winner that put Fulham out of the FA Cup in March and scored again when Southampton claimed Arsenal's scalp in April.

On Saturday evening, Stewart will feature in the semi-final against Manchester City. The fact that Stewart is barely mentioned as a possible squad player in America is nuts.

This season, he's scored a goal every 120 minutes with a shots–per-goal figure of 3.2. He has a conversion rate of 31%. That's remarkably high. When he plays, he's been one of the-most efficient goalscorers in the entire league.

Clarke believes in loyalty to his players, to the ones who got the team to the World Cup in the first place. Stewart is not one of those guys, but on form he could be the kind of striker to help keep Scotland in America beyond the group stage.

The head coach needs form players, not protected species. Red carpets should not be rolled out for time served.

When McBurnie scored for Hull at Leicester on Tuesday night, it was his 16th goal in 37 games for the Championship team this season, a run, in all competitions, that also includes seven assists. For a Scottish striker who missed two months of the campaign through injury, it's an impressive return.

To drill down a little, this season, McBurnie has scored every 182.9 minutes for his club and has a goal from every 4.3 shots and a conversion rate of 23.5%.

Recently, he contacted Clarke to see if he had any hope of making the World Cup squad. The way McBurnie tells it, Clarke's answer didn't give him a whole lot of encouragement. The head coach can't afford to be as dismissive as McBurnie made him sound.

Many of those who remember what McBurnie was like when he played for Scotland would, no doubt, agree with Clarke on this, if McBurnie's recounting of their conversation is accurate. Under Alex McLeish and in the early games under Clarke, McBurnie had his chance and he didn't take it.

Sixteen caps (seven starts) and no goal. More than that, in nearly 13 hours of action, Scotland only scored once while he was on the pitch. He was also once embroiled in controversy around his commitment to the cause.

Fairly or unfairly, you may have to go a long way to find a Tartan Army member who's calling for his return. Forgiveness drops slowly.

It's been five years since he last played for Scotland. That's a fair old penance. Maybe he's a better player and a better person than he was then.

Nobody is expecting him to play for Scotland ever again, but if Clarke has already closed his mind to Stewart and McBurnie then he's ignoring two players performing with huge amounts of confidence and scoring plenty of goals. What else can they do?

Shankland is third on the list above and is a shoo-in for the squad and a front-runner for the team if form counts. Hirst is fourth. He showed up well in the friendly against Ivory Coast, in the first half at any rate. He looked hungry and powerful, his appetite for work was unmissable.

He has 10 goals in 41 games for Ipswich, who are currently second in the Championship with a game in hand over the ones behind. He's operating at a high level. The Premier League awaits if Ipswich keep their nerve.

Hirst's conversion rate is 14.7%, behind Shankland's 18.7% but ahead of Bowie on 13.6% and Adams on 13.2%. Conway and Dykes bring up the rear on that front. The case for Dykes' inclusion looks weak if you're going solely on what's happening in the here and now.

Luckily for him, his bid is probably compelling in the only place that truly matters - in the mind of the Scotland manager.

You'd imagine that Clarke already knows the final 26 - or very close to it. Stewart and McBurnie won't be in it.

In the stats they're one and two. In Clarke's estimation they're probably about seven and eight, if they're ranked at all.

Maybe he should revisit that. The evidence is all there should he decide to study it.