About this opening
Four Knights Game: Spanish Variation, Symmetrical Variation, Metger Unpin is an opening in the Encyclopedia of Chess Openings,
classified under code C49. ECO group C (C00–C99)
covers open games (1.e4 e5) and the French Defence, including the Ruy Lopez, Italian, Scotch and King's Gambit. This particular variation is reached
after 16 half-moves from the
starting position, with the move sequence 1. e4 e5 2. Nf3 Nc6 3. Nc3 Nf6 4. Bb5 Bb4 5. O-O O-O 6. d3 d6 7. Bg5 Bxc3 8. bxc3 Qe7.
It belongs to the Four Knights Game family.
Within that family this is a level-3 branch (the Spanish Variation → Symmetrical Variation → Metger Unpin line). The immediate parent line is Four Knights Game: Spanish Variation, Symmetrical Variation, transitioned via 8…Qe7.
The opening sequence in prose form: 1.e4 e5, 2.Nf3 Nc6, 3.Nc3 Nf6, 4.Bb5 Bb4, 5.O-O O-O, 6.d3 d6. From this position the encyclopaedia records no further canonical continuations — practical play branches into unnamed transpositions or returns to the parent line for alternative ideas.
Use the interactive board above to walk through the moves position-by-position. Click any move in the navigation to step backwards, or use the keyboard arrow keys. For statistical data — how often master-level players have reached this position, White's win-rate, draw frequency, Black's score — see the panel in the right column.
Caissly's coverage of C49 extends through every named sub-variation in this line and across all four locales (English, Spanish, Portuguese, Russian). Where editorial commentary exists for a specific variation it appears as the page body; otherwise the page presents the structural data, board, and statistics as shown here.