Sergash: Kristian Trygstad is a Norwegian FIDE master, born on August 11 1978, so he was 23 years old at the time of this game. Carlsen was 11 years old and a chess Expert.
<6.d2-d4!> Probably the best move, so Carlsen possibly had studied his previous game with this position? In that previous game, played that same year, Carlsen had played 6.Nb1-c3 e7-e5 7.d2-d3 Nb8-c6 8.Ra1-b1 a7-a5 9.a2-a3 h7-h6 10.b2-b4 a5xb4 11.a3xb4 Bc8-e6 12.b4-b5 Nc6-e7 13.Nf3-d2 Qd8-c8 14.Rf1-e1 Be6-h3 15.Bg2-h1 Nf6-g4 16.Nc3-d5 Ne7xd5 17.c4xd5?! f7-f5 18.Qd1-c2 Qc8-d8?! 19.b5-b6 c7xb6 = Carlsen vs D Kedyk, 2002, draw.
<6...Nb8-d7 7.Nb1-c3 e7-e5 8.e2-e4 a7-a6 ⩲> The most played move. The computer (Stockfish 14 AVX2 64 bits) prefers the attack on the centre with 6...c7-c5 by transposition Maroczy vs S Landau, 1930, 1-0; and also the development of the bishop 6...Bc8-f5 (A Selezniev vs Euwe, 1923, 1-0).
<9.Rf1-e1 e5xd4 10.Nf3xd4 ⩲> The most played move here, historically speaking, has been 9.h2-h3 ⩲ R.F. Streater vs. Alan Phillips, Great Britain Championship 1954 in Nottingham, round 9, 0-1.
<10...Rf8-e8?! ±> Trygstad doesn't seem prepared enough in the opening. More precise seems 10...Nd7-e5! 11.b2-b3 c7-c5 ⩲ M Vukic vs A Planinc, 1976, 1-0.
<11.f2-f3? Ra8-b8 => Shutting down the white bishop on g2 is not a good idea. 11.b2-b3! ± Δ Bc1-b2 Goran Dizdar (2490) vs. Zoran Ilic, 40th Yugoslavia Team Championship 1988 in Brezovica, draw.
<12.Nd4-e2N? Nd7-e5! 13.b2-b3 ∓> A new move and a second consecutive serious mistake, showing that White doesn't possibly understand this position well. Several moves are playable here that maintain equality:
A- 12.b2-b3 = with a possible Bc1-b2. Sudhir Kumar Sinha (2168) vs. Andika Pitra (2303), Kuala Lumpur Open (Malaysia) 2011, round 8, 0-1.
B- 12.a2-a4 = Pascal Flierl (2241) vs Martin Krockenberger (2208), League Germany BL2-Süd 07-08 2007, Schwegenheim vs Schmiden Cannstatt, round 3.6, 1-0.
C- 12.f3-f4 = Rita Zykiene vs Renata Turauskiene (2200), Lithuania Women Champonship 1996 in Marijampole, round 10, 1-0.