{"id":1718,"date":"2012-09-06T09:11:47","date_gmt":"2012-09-06T17:11:47","guid":{"rendered":"http:\/\/www.danamackenzie.com\/blog\/?p=1718"},"modified":"2012-09-06T09:17:40","modified_gmt":"2012-09-06T17:17:40","slug":"knights-are-tricky","status":"publish","type":"post","link":"https:\/\/danamackenzie.com\/blog\/?p=1718","title":{"rendered":"Knights are Tricky"},"content":{"rendered":"

The U.S. Chess League started its eighth season this week, and for the first time I watched online at chess.com<\/a>. (Thanks to Gjon Feinstein for tipping me off to the fact that the games were being streamed there.) I mostly followed the San Francisco – Carolina match, in which the San Francisco Mechanics were heavy rating favorites but had to scramble just to pull out a 2-2 tie.<\/p>\n

The crucial matchup turned out to be on board 2, where GM Jesse Kraai had Black against FM Kassa Korley. It was a must-win for the Mechanics, who were now trailing 1-2. Korley made a bad choice to put his bishop on g6, and they arrived at the following position:<\/p>\n

\"\"<\/a>

White to move.<\/p><\/div>\n

FEN: 8\/4r1p1\/5pBp\/2k2P2\/3p4\/1Pn2KP1\/3R1P2\/8 w – – 0 1<\/p>\n

Korley played 1. Bh7, understandably trying to get his bishop back into play via g8. But he ran afoul of the marauding knight! Jesse slammed down the move 1. … Ne4! There’s a hidden threat here that Korley didn’t see, and he played 2. Rd3??, allowing Jesse to play 2. … Ng5+ forking the king and bishop. White resigned.<\/p>\n

Of course White had to play 2. Rc2+. You might enjoy trying to work out the win for Black. (According to Rybka, the correct reply is 2. … Kb6!, whose main virtue is that it doesn’t get in the way and doesn’t walk into possible checks like Rc4+ and Bc4+.) However, the main thing I want to talk about is how the game DID finish. Why did White walk into this knight fork?<\/p>\n

There’s one other key fact I haven’t told you, which is that White only had a minute left on his clock. That’s not quite as bad as it sounds, because the USCL games are played with a 30-second time increment — but it nevertheless means that White was under considerable time pressure.<\/p>\n

I think that what this example shows is that even for strong masters — Korley is in the high 2300s — knight moves are a little bit tricky. It just isn’t immediately obvious that a king on f3 and a bishop on h7 are in a forkable position. If Korley had had more time and been under less pressure, of course he would have seen it. But when you are harried and only have a few seconds to move, knight forks are the first thing that you start to overlook<\/em>.<\/p>\n

I think this observation has practical significance. If you find yourself playing against a knight when you’re in a time scramble, you should make a mental note to consciously check<\/em> for knight forks before you move. You can’t just go by intuition. You have to deliberately look for them.<\/p>\n

Here’s another example that was extremely fresh in my mind, because it happened in my last-round game this weekend against Praveen Narayanan! We reached the following position in a time scramble. I have 9 minutes left for the game and he has 4 minutes. I’m playing Black.<\/p>\n

\"\"<\/a>

Position after 53. Kg4. Black to move.<\/p><\/div>\n

FEN: 8\/p7\/Pp1p1rk1\/1Pp2N2\/4P1K1\/3P3P\/8\/8 b – – 0 53<\/p>\n

I don’t know whether Black should be winning in this position, but I doubt it. However, during the game I thought I was winning, and I played 53. … d5??<\/p>\n

Of course, what I missed was the knight fork, 54. Ne7+! Here is where I played 54. … Kh6 and offered a draw, which my opponent declined. Then Narayanan played 55. Nxd5?, which was possibly a mistake. It allowed me to activate my rook with 55. … Rf1. I think he should have played 55. ed instead. But in a time scramble, who can tell?<\/p>\n

Anyway, after a few more moves the knight once again rose from the dead, like a zombie. Here’s the position:<\/p>\n

\"\"<\/a>

Position after 64. Nc4. Black to move.<\/p><\/div>\n

FEN: 8\/p3Pk2\/P1K5\/1P6\/2N5\/2pr4\/8\/8 b – – 0 64<\/p>\n

The clocks now show 30 seconds or so for White to 1:30 for Black. White has just moved his knight from b6 to c4, a seemingly innocent move that merely gets the knight out of the way of the b-pawn. But Black just pushes his pawn to c2 and queens first, right?<\/p>\n

WRONG!! In fact, 64. … c2??? would have been a blunder for the ages, as it lets White fork the king and rook AND win the rook AND defend the c-pawn, with 65. Ne5+ Kxd7 66. Nxd3.<\/p>\n

Believe it or not, I actually started moving my hand to push the c-pawn, but something held me back at the last moment. I think that it was the memory of the earlier knight fork, just 10 moves ago, that made me say, “Hold it, can he play a fork here?” In a strange and miraculous way, my earlier blunder prepared me subconsciously to avoid a much worse blunder here.<\/p>\n

I withdrew my hand, took a deep breath and played 64. … Ke7! instead. Narayanan then played 65. b6? c2 66. b7 c1Q 67. b8Q Qxc4+ and White resigned. Whew!<\/p>\n

Actually, he could have still made matters tricky for me with 65. Na3! but that’s a subject for another time.<\/p>\n

There’s an old saying, “Knights on the rim are dim.” I would like to add a new one: “Knights in time trouble are worth double.”<\/p>\n","protected":false},"excerpt":{"rendered":"

The U.S. Chess League started its eighth season this week, and for the first time I watched online at chess.com. (Thanks to Gjon Feinstein for tipping me off to the fact that the games were being streamed there.) I mostly followed the San Francisco – Carolina match, in which the San Francisco Mechanics were heavy […]<\/p>\n","protected":false},"author":80,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[1363,10,16,31],"tags":[2304,88,307,2302,2303,1140,2104],"class_list":["post-1718","post","type-post","status-publish","format-standard","hentry","category-current-news","category-endings","category-positions","category-us-chess-league","tag-aphorisms","tag-forks","tag-jesse-kraai","tag-kassa-korley","tag-praveen-narayanan","tag-san-francisco-mechanics","tag-swindles"],"_links":{"self":[{"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1718","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=\/wp\/v2\/users\/80"}],"replies":[{"embeddable":true,"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1718"}],"version-history":[{"count":2,"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1718\/revisions"}],"predecessor-version":[{"id":1723,"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1718\/revisions\/1723"}],"wp:attachment":[{"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1718"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1718"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/danamackenzie.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1718"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}