Affordable Computer Chess Tournament - QUARTER-FINALS

[TracySMiller]

Both units played a little sloppy, but no major blunders. Tough endgame, but with precise play, the Novag Citrine could have won this, being a pawn up, according to Stockfish. Here's a position where an inaccurate move saw White's evaluation drop from +2.8 to +0.4.

[fen]8/5p2/1p2p2p/3kP3/P2b1PPP/3R1K2/7r/2N5 w - - 9 61[/fen]

The correct move is Kg3, but white played Nb3. The Novag Citrine still leads the match 5.0-3.0.

Here's the game: https://lichess.org/p8L0l3RW#0

[TracySMiller]

Another tough endgame, but White made a couple of crucial blunders, and the Novag Citrine takes a commanding 6.0-3.0 lead in the match. Here was the worst of the blunders:

[fen]3r2k1/5p1p/p1R3p1/4Q3/1q6/3p2P1/1P3PKP/8 w - - 2 42[/fen]

White has to play Rc1 to try to stop the passed d-pawn, but after Rc7, the passed pawn has no problems deciding the game.

Here's the game: https://lichess.org/zlRlHB0a#0

[TracySMiller]

Unfortunately, I didn't even recognize that game 9 was a duplicate of game 1 (at least through the first 45 moves or so), so I'm going to void that game. Strangely, the moves did diverge near the end, but well past where the game had been decided.

All that time wasted. SIGH. Well, anyway, Novag Citrine leads the match 5.0-3.0.

[paulwise3]

Hi Tracy,

Don't worry and keep up the good work! I have both the Citrine and the Grandmaster, and am very interested in this match. Considering the big elo-difference I think the Grandmaster does quite well.

Best regards,
Paul

[TracySMiller]

The Excalibur Grandmaster had the Novag Citrine on the ropes and couldn't put him away. Frustrating to see the GM have such a huge advantage and not be able to figure out how to win. So both sides just shuffled their Kings, Queens, and Rooks around until hitting the Draw by 50-move Rule. Novag Citrine leads the match 5.5-3.5.

Here's an example of what an overpowering position Excalibur GM had (playing White):

[fen]r3r3/2P2pk1/3Q2p1/3KP2p/7P/p5P1/P7/8 w - - 4 46[/fen]

Stockfish was rating White's position as +7.0 here!

Here's the game: https://lichess.org/euZgKL8T

[TracySMiller]

The Novag Citrine developed a powerful attack in the center against Black's uncastled King. Black made some mistakes and before you know it, the Novag Citrine has built up an almost insurmountable 6.5-3.5 lead in the match. Here's an example of black playing poor moves:

[fen]q3kr2/7p/1prp1pp1/4p3/4PPb1/PQN5/1PP3PP/4RRK1 w - - 9 24[/fen]

On the previous move, Black had a chance to get the White Queen off this powerful a2-f8 diagonal with Be6, but after the passive Ke8, White seals the deal with 24. f5!, cutting off the Black bishop from defending, and allows the Bishop to be trapped a few moves down the road.

Here's the game: https://lichess.org/HDE6ewQB

[TracySMiller]

The Novag Citrine gets an early advantage due to some inaccurate moves by the Excalibur Grandmaster, but after some inaccurate moves of its own, its advantage slips away into an opposite-colored Bishop endgame. Here's the early position where Black uses that tactic of attacking the piece that is defending another piece.

[fen]4r1k1/pp1b1pp1/3b2qp/R6N/3p4/1P1P3P/1PP2PP1/2BQ1K2 w - - 1 21[/fen]

Black plays Bb4, attacking the Rook that is defending the Knight on h5.

After the game reached the opposite-colored Bishop endgame, rather than spend the next hour watching Bishops and Kings move hopelessly around the board, I adjudicated the game a draw. Novag CItrine leads the match 7.0-4.0.

Here's the game: https://lichess.org/CC5ySWkM#0

[TracySMiller]

The Novag Citrine moves to within half a point of advancing to the Semi-Finals with this tactical victory. The Excalibur Grandmaster tries to shake things up by playing the Grunfeld Defense, but the Citrine was up to the challenge. The Exacalibur GM gets sloppy and allows its Queen to get trapped, and it was all Citrine after that.

[fen]rnbr2k1/pp3p1p/5bp1/3Pp3/q3PP2/2BB4/P2QN1PP/1R3RK1 w - - 0 18[/fen]

In this position, Black must retreat its Queen to e8, but after Nd7, White plays Bb5, then after Qxe4, Ng3, the best Black can do is get a Rook for its Queen. The Novag Citrine now leads 8.0-4.0

Here's the game: https://lichess.org/13vm5cqd

[TracySMiller]

The Novag Citrine becomes the first unit to advance to the Semi-Finals by taking advantage of 7 GM mistakes to only one itself. The final score is Novag Citrine 9.0, Excalibur Grandmaster 4.0. Here is the turning point of the match:

[fen]r1b1r1k1/pp1p1ppp/2p5/1P1P4/4P3/2QB1P2/q5PP/1N3RK1 w - - 0 19[/fen]

White can perhaps trap the Black Queen with Na3, but after playing dxc6, Black gets its Queen back into the game and rolls over the Excalibur GM.

Here's the game: https://lichess.org/cOkH54Z6#0

As a reminder, here is the spreadsheet with the Tournament results: https://docs.google.com/spreadsheets/d/ ... sp=sharing

[TracySMiller]

Since Spacious_mind predicted a 9-3 victory and paulwise3 predicted 8.5-2.5, I suppose I have to give the first match prediction point to spacious_mind (barely).

Next up will be the wonderfully powerful RadioShack 2250XL against the little known and little owned RadioShack Chess Master.

But first, I'm going to take a two-week break from chess computers to focus on getting ready for the USA Memory Championship Qualifiers (my other hobby is memory sports). I'll be back soon!

[paulwise3]

I hope Tracy's memory brings her back soon on this site to continue this tournament...

Sweet memories regards,
Paul

[TracySMiller]

Yes, I am back, and I'm a dude, not a dudess. BTW, I finished seventh in the USA Memory Championship qualifiers, and now join 12 other finalists in the Finals, to be held at MIT in Cambridge, MA on 07/14/18.

I've played the first three games of the RS Champion 2250XL vs. RS Chess Master match so far, and surprisingly the Chess Master is leading 2-1. White has won all three games. I'll get the games and my analysis uploaded sometime tomorrow.

[TracySMiller]

RS Chess Master starts out with a nice game as white, with just 3 mistakes and no blunders, compared to the 6 mistakes and 2 blunders of the RS Champion 2250XL. It involved a tough endgame, the type that dedicated computers have a hard time with.

In this position, black played the seemingly harmless bxc5, but after the bxc5 recapture, white gains a passed pawn which ends up consuming black's attention while white gobbled up the black pawns.

[fen]6k1/p2N1ppp/1p1np3/2P5/1P6/P3P3/5PPP/6K1 w - - 0 23[/fen]

Here's the game: https://lichess.org/uSaOnSfZ

[TracySMiller]

This time it was RS Chess Master's turn to be sloppy, making 9 mistakes and 2 blunders, and the RS Champion 2250XL tactically mopped the floor. Here's a key position:

[fen]1r2kb1r/pbQn1ppp/2p1p1q1/1p6/3P4/2N1P3/PP1N1PPP/2R1KB1R w Kk - 6 15[/fen]

In this position, white made the nice tactical shot Nxb5!. Black can't take with the pawn, for after Bxb5, Black has a huge problem on its hands, and must protect the d7 Knight with its Rook, thus losing the Bishop on b7.

Here's the game: https://lichess.org/mYbZrGvD

[TracySMiller]

RS Chess Master retakes the lead with another nice game, making only 2 mistakes and 1 blunder.

[fen]1r1q2k1/3p1ppp/1Nb5/p1P2r2/1P2p3/P1Q1P3/5PPP/3RR1K1 w - - 5 33[/fen]

In this position, white played bxa5, creating an advanced passed pawn that would end up deciding the game.

Here's the game: https://lichess.org/HvR8S4v2