Coach definition, not a live verdict. These pages show how the X-ray Coach defines this concept and where its thresholds sit, sourced from the coach's own code. Unlike the tactic pages, nothing here runs a live detector — example boards illustrate the rule, they don't execute it.
What it means
- The coach flags when a move *creates* an isolated pawn — one with no friendly pawn on either neighbouring file, so no pawn can ever defend it.
- As with doubled pawns, each event carries an engine-judged outcome; an isolated pawn is not automatically a mistake.
The exact rule the X-ray Coach applies
- Fires on a 1-ply set-delta: a pawn that had a neighbour-file pawn before the move has none after it (self side and opponent side both tracked).
- Same outcome taxonomy as doubled pawns: created-ok / created-avoidable / missed / avoided-smartly / irrelevant / unknown.
Why it matters
An isolated pawn is a permanent target and concedes the square in front of it — but it also opens lines and grants activity, which is why the engine verdict, not the structure alone, drives the score.
Example
the highlighted pawns
The d4 pawn is isolated — there is no white pawn on the c- or e-file, so no pawn can ever defend it. (The a2/b2 pawns are connected.)