Season 19 qualification league

Season 19 started with a qualification league with 12 engines, 1 and DRR, 30+5 time control.

The engines playing in the qualification league are:

- Played in season 18: Asymptote, Monolith, chess22k, ChessFighter, FabChess, Combusken, Tucano, Bagatur, Weiss
- New engines:  SlowChess Blitz Classic, A0lite, Roc

Final standings

SlowChess and Roc promote. SlowChess was much better than the rest of the field, it will be interesting to see how far it can go. The race for 2nd place was close and continued until the very last round. Roc is apparetly related to Gull, so it is nice to see it back in TCEC.

A0lite, Bagatur and Tucano lost more than half of their games against the rest of the engines. A0lite seems to be a small NN experiment (running on CPU? I think), it usually started games well but failed miserably at the end. Maybe it will improve until next Season. 

League 3 is next, SlowChess and Roc will play together with:

Gogobello, Igel, Minic, iCE, Marvin, Topple, Pirarucu, and Counter (all from season 18 league 3).

Interestsing games

 

Game 12, SlowChess - chess22k: SlowChess gave two pawns to create an advanced passer in a RRB vs RRB position. Exchanging the rooks resulted in a second connected passer and a win.

Game 14, Monolith - SlowChess: SlowChess used a pawn majority on the queen side in a RRN vs RRN position to create an unstoppable pawn.

Game 23, SlowChess - Roc: Roc realized its king was in danger too late and lost its queen.

Game 35, chess22k - FabChess: chess22k was up a bishop for 2 pawns with evals over 2. FabChess captured all the white pawns and forced a draw.

Game 36, Monolith - Roc: Roc attacked on the queen side and gradually increased the pressure. After a series of exchanges the game reached a R vs BN ending and Roc slowly converted the win.

Game 38, FabChess - Monolith: The game reached a RB vs RBN position, white with a passer on the 7th rank. Monolith blocked the passer and attacked the white king, it used a mate threat to capture the bishop and reduce to a pawnless tablebase win.

Game 47, Monolith - ChessFighter: In a RN vs RN position Monolith captured the knight for two pawns, then managed to convert with one pawn remaining.

Game 59, Roc - Combusken: Combusken opened the king side and attacked the white king, it was a rook up after a series of exchanges, enough for a win.

Game 65, Tucano - chess22k: chess22k gave a rook for a bishop to lower the pressure on its king, Tucano gave the material back and reduced to a B vs N ending with an advanced passer. Eventually both engines queened a pawn, Tucano was first and this was enough to secure the win.

Scores after 11 rounds: SlowChess +7, Roc FabChess Monolith +3, chess22k ChessFighter Combusken +1, Asymptote Weiss -1, Bagatur Tucano -5, A0lite -7. SlowChess is the strongest engine in the league, it will probably be this league's winner. There is a close race for 2nd place, probably one of the 6 engines in places 2-7 will promote to league 3. The 3 engines at the bottom are the punching bags of the league, each losing more than half of its games against the higher placed engines.

Game 75, FabChess - Bagatur: FabChess was better with an eval over 2.5 but it let Bagatur reduce to a drawn rook ending.

Game 78, chess22k - SlowChess: An unusual blunder by chess22k early in the game gave SlowChess a R vs Q advantage, the game was adjudicated on move 22.

Game 80, SlowChess - Monolith: The black queen came forward and was almost trapped, by the time it got out SlowChess was up a piece with a strong bishop pair that ensured the win.

Game 85, Asymptote - A0lite: Asymptote sacrificed a knight and a rook and attacked the black king, then it got the move order wrong and A0lite was suddenly safe and up two pieces. A0lite got its first win in the league.

Game 88, FabChess - Weiss: Weiss dominated the queen side in a BN vs R imbalance. It used a passer to capture a knight and reduce to a winning N vs R ending.

Game 93, SlowChess - FabChess: FabChess blundered in a drawn B vs N ending.

 

Scores after 16 rounds: SlowChess +11, Roc +6, Monolith +4, Combusken +3, ChessFighter +2, FabChess chess22k +1, Asymptote -1, Weiss -2, Tucano -7, Bagatur  A0lite -9. Roc improved its chances with 3 wins, FabChess dropped after losing two games and missing opportunities against weak engines. Combusken and Monolith are also in the leading group. There are 6 rounds to go, the race for 2nd place is still open.

Game 103, A0lite - Roc: A0lite was 3 pawns up in an opposite color bishop ending. A better engine would have won but Roc managed to survive.

Scores after 19 rounds: SlowChess +13, Roc +7, Monolith Combusken +5, ChessFighter +1, chess22k +0, FabChess -1, Asymptote Weiss -2, Tucano -6, Bagatur  A0lite -10. Only 3 rounds to go. Monolith and Combusken still have a small chance to finish ahead of Roc.

 

In round 20 Roc beat ChessFighter while Monolith and Combusken drew their game. Roc increases the lead to 1.5 points with 2 rounds remaining.

 

Game 125, Combusken - Roc: The black king was uncastled and had to walk to safety. Combusken used the time to build a strong queen side and to create a central passer. Eventually the advantage was converted into material, Combusken went up a rook and won.

Combusken closed the gap to 0.5 points, Monolith drew against Asymptote. The scores before the last round are: Roc +7, Combusken +6, Monolith +5.

 

Combusken and Monolith drew their last games, Roc ended with a win and secured 2nd place.