Scotland are on the verge of securing second place in their World Cup Qualifying group, only requiring one more win to make it.

They come up against a Moldova side ranked 181st in the world, making them the 4th weakest team in Europe. If Scotland can overcome the minnows, a place in the playoffs awaits with a World Cup in sight for the first time since 1998.

Steve Clarke has kept a stable squad which has changed little over the last few years. Although this has been successful, players that have started performing exceptionally in the meantime have been omitted. Pros such as Ryan Gauld, Aaron Hickey, Johnny Russell and, of course, Tony Ralston will feel hard done by as they see their top form go unrewarded. This, combined with the deteriorating form of other players makes Clarke’s squad decisions all the more frustrating.

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But the selection that sticks out most is that to pick Stephen O’Donnell over Ralston. O’Donnell has been having a torrid season for Motherwell so far, with his side only winning one out of nine matches Premiership matches when he’s been involved. In contrast at Celtic, the Ralston renaissance has been ongoing since Ange took charge, already amassing four goals and four assists across around 2,500 minutes of game time.

Statsbomb gives a clearer insight when comparing the two. In terms of output, Ralston has 0.41 xG+xA which is four times larger than the 0.1 xG + xA p90 O’Donnell has generated so far this season.

The fullback radar charts on Statsbomb give a good indication of the difference in quality available to Clarke.

Celtic Way:

When comparing the two defensively, the Celtic man comes out on top, often by drastic proportions. Tack/Dribbled Past%, which is the percentage of times a player makes a tackle when going into a duel vs. getting dribbled past, goes overwhelmingly in Ralston’s favour 91% (99th percentile) to 64% (35th percentile). This means from a defence perspective, Ralston is bypassed significantly less often. One strength that O’Donnell brings to the Scotland starting eleven is aerial presence, but when comparing performances this is another factor by which he is outclassed by Ralston. Aerial wins per 90 minutes (p90) go 3.43 to 1.93 in Ralston’s favour. For PAdj interceptions and PAdj tackles, Ralston ranks in the 98th and 99th percentile respectively compared to 62nd and 6th. The only area O’Donnell performs better defensively is that he gives away fewer fouls, 1.2 to 0.97 p90.

On the ball, unsurprisingly under Ange-ball, Ralston has far exceeded his international full-back competition. Nowhere is the quality difference starker than pass completion percentage where the Celtic right-back beats out his rival 82% (89th percentile) to 67% (14th percentile). In terms of xGBuildup, the same can be seen again with 1.09 p90 (99th percentile) compared to just 0.21 p90 (12th percentile). Deep progressions as well show the difference with the Celtic man nearly completing double, 9.35 to 5.91.

The most ridiculous metric is successful dribbles in which O’Donnell is yet to complete a single one after 9.3 90 minutes so far this season. This has no doubt been an area where Ralston has thrived completing an astonishing 1.29 dribbles p90.

On the ball, the only area O’Donnell is stronger is with turnovers where he loses possession slightly less often than Ralston, 1.89 to 1.4.

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Overall, the decision to omit Ralston in favour of O’Donnell is baffling.

I can't see any justification to be picking a full-back nearing 30 and in a poor run of form. Clarke has his favourites but the national team has access to data sources that should be able to help him make these decisions. I could understand omitting Ralston at the last international break as the sample size was smaller, but we now have 2,500 minutes of positive performance data to go by which makes the omission frustrating and undeserved.

Clarke has focused on squad cohesion which has worked, but quality performances must be rewarded and being in the previous squad shouldn't mean a guaranteed selection.

No matter Clarke’s decision, for Anthony Ralston his Scotland call up is more a matter of when and not if which at the start of the season seemed an impossible thought.