Does squad depth matter more than a settled starting XI?

What does the number of changes tell us?

Galatasaray used a different starting XI in each of its first ten league games and led the table with 25 points. Erzurumspor FK kept the previous league XI unchanged in five of nine comparisons and collected 14 points. It would be easy to take those two examples as an argument for constant rotation. But if the player Galatasaray leaves out is not comparable with Erzurumspor FK’s available replacement, what are we actually comparing?

Squad depth has to be part of the answer. A team’s ability to change players and the effect of those changes on the pitch are separate questions. A strong, broad squad can give a coach several players capable of doing the same job. In a more limited squad, repeatedly starting the same players may reflect necessity rather than a deliberate preference for continuity. This time, we therefore looked not just at changes, but also at how squad value and playing time were distributed.

How many players are there, and how many are trusted?

First, squad size and squad quality need to be separated. Our valuation snapshot lists 32 players for Galatasaray and 27 for Erzurumspor FK. That five-player difference does not tell us enough about the quality of the alternatives. Both clubs also gave league minutes to 24 different players in their opening ten games. Simply counting the players used gets us no further in this comparison.

For a more revealing measure, we selected each club’s eleven players with the most league minutes. This is not a preferred formation: positions played no part in the selection. We added those players’ published market values and divided by the total squad value in the same source snapshot. This shows how much of the squad’s published value sits with its most-used players.

Galatasaray’s eleven were valued at €231.5 million, or 60.7% of the total, leaving €150 million in published value outside that group. Fenerbahçe’s core accounted for 56.9%, with €112.7 million outside it; Beşiktaş’s figures were 54.8% and €123.5 million, and Trabzonspor’s were 54.5% and €83.9 million.

All four clubs had considerable economic resources beyond their most-used eleven. That does not mean every remaining player was fit, ready or a realistic option for the coach every week. This remainder should not be read as the value of the available matchday bench.

Why Erzurumspor FK shows the limits of a percentage

At Erzurumspor FK, the most-used eleven accounted for just 33.5% of published squad value. On that percentage alone, we might conclude that value was broadly spread and that the squad was particularly deep. Yet the published value outside those eleven was €15.4 million, roughly a tenth of Galatasaray’s €150 million.

Similar percentages can therefore conceal very different resources. An alternative-player pool worth 40% of a €380 million squad is not equivalent to 40% of a €23 million squad. Market values also reflect factors such as age and resale potential, so a more expensive player is not automatically a better performer in every match.

These figures cannot establish why Erzurumspor FK made fewer changes. Playing time gives us a clearer observation: the club’s eleven most-used players accounted for 83.6% of all minutes actually played. That share was 76.5% at Galatasaray, 76.9% at Fenerbahçe, 79.2% at Beşiktaş and 78.7% at Trabzonspor. Despite using the same number of players as Galatasaray, Erzurumspor FK concentrated more of its workload on a smaller core.

Changing the XI is not the same as making substitutions

Our next question was how long the players who started each game stayed on the pitch. For every match, we added the minutes played by the eleven starters and divided by eleven. We then expressed that average as a percentage of the regulation 90 minutes. An average of 81 minutes per starter means 90% on this measure.

Across the league, a starter played an average of 81.2 minutes, or 90.3% of regulation time. Galatasaray’s average was 80.9 minutes (89.8%), Fenerbahçe’s 81.8 (90.9%), Beşiktaş’s 81.5 (90.5%) and Trabzonspor’s 81.4 (90.5%). Erzurumspor FK averaged 82.8 minutes, or 92.0%.

Changing the starting lineup every week did not mean Galatasaray routinely took that day’s starters off early. Nor did Erzurumspor FK’s more settled starting XI mean it finished every game with the same eleven. Changes between starting lineups, the timing of substitutions and the distribution of the season’s workload are three different measures. Treating them as interchangeable obscures what happened.

How can we reduce the effect of squad quality?

Rather than compare Galatasaray directly with Erzurumspor FK, we first compared each club with itself. We separated games with no more than two changes from the previous league XI from games with three or more. This removes differences between clubs’ underlying strength from the basic comparison.

Galatasaray averaged 2.25 points in its four lower-change games and 3.00 in its five higher-change games. Fenerbahçe’s averages were 1.20 and 2.50, and Trabzonspor’s were 1.80 and 3.00. Beşiktaş went the other way: 2.00 points in five games with at most two changes, compared with 1.50 in four games with more changes.

Giving each of the eighteen clubs equal weight produced averages of 1.26 points for the lower-change group and 1.81 for the higher-change group. That is not a prescription to change three players and win more games. Erzurumspor FK’s higher-change group contains only one match, while several other clubs have groups of just two. Opponents, venues and the timing of European games still differ.

We ran an additional check that compared each club with itself while also accounting for venue, opponents’ points averages against other teams, and returns from Europe. The positive relationship between more changes and more points remained. This did not support the claim that fewer changes brought more success, but it did not fully remove squad-quality differences or identify points gained through rotation either.

Even the same club did not have the same options every week. Replacing Osimhen need not carry the same implications as a change elsewhere. A change forced by injury or suspension is also different from a choice to rest someone. Without player-level availability and the strength of the actual starting lineup, adding total squad value to a model cannot resolve all those differences.

Europe put different demands on the same squads

In the four major clubs’ fifteen league games following Europe, changes from the previous league XI averaged 3.47. In the other twenty-one comparisons, the average was 1.90. All four clubs made more changes after Europe. High rotation cannot therefore be attributed solely to a coach failing to settle on a team: the player pool was being used to handle a busier schedule.

That puts the valuation comparison into context. Galatasaray, Fenerbahçe, Beşiktaş and Trabzonspor all had substantial published value outside their most-used eleven, and drawing on that pool during a European campaign is understandable. It does not establish that every change was voluntary rest or that every change worked.

Research also considers rotation alongside squad strength. A study of 16,720 games in four major European leagues examined the relationship between rotation, points and squad market value. Its published abstract reported that the relationship between rotation and success strengthened as squad value increased. This helps explain why prescribing the same amount of rotation for every team makes little sense; it does not validate our ten-game sample.

What do you lose when you make a change?

The opening ten games did not support the rule that keeping the same XI brings success. Galatasaray changed more players and led the table; Beşiktaş collected fewer points in its higher-change games. Erzurumspor FK concentrated more of its playing time on a smaller core. Labelling all of these choices as either stability or instability does not explain the different circumstances.

The more useful question is how much of a team’s game changes when one player replaces another. Squad value and its distribution offer a starting point. Playing time shows how much of that pool the coach actually used. But without injuries, player roles and the quality of each match’s starting lineup, we still cannot say that making more changes is better in itself. The conclusion is to stop treating fewer changes as a success metric and instead assess the available alternatives alongside what happened on the pitch.