This game continues the recent theme of an English Opening with e3/b3 development from last time (Carlsen - Giri), but here GM Ian Nepomniachtchi as White plays the provocative yet thematic 7. g4!? to completely change the character of the game. Pitching the g-pawn in this manner is one example of similar themes appearing across different openings - as occurred in a previous Caro-Kann commentary game - so the idea is well worth studying. I'm not sure if I would play it myself, but improving your chess strength requires having a more open mind to study ideas that are outside your normal comfort zone. In my previous (pre-blog) chess career, for example, I never would have looked at this game in depth, one of the reasons I stagnated at Class B strength for so long.
Of course 7. g4 does not magically win straight out of the opening, but White does well for himself in gaining the initiative and minimizing his positional weaknesses, with his king position being reasonably solid in the center. Anand does eventually equalize, but then Nepo strikes back and is able to pick up material for no compensation. Black, left with the prospect of a losing endgame with no counterplay, resigns. I doubt this would happen at the club level, but it's worth seeing in the final position what a 100% sure win looks like, even with a fair amount of material still on the board.
[Event "9th London Chess Classic 2017"]
[Site "London"]
[Date "2017.12.09"]
[Round "7"]
[White "Nepomniachtchi, Ian"]
[Black "Anand, Viswanathan"]
[Result "1-0"]
[ECO "A17"]
[WhiteElo "2729"]
[BlackElo "2782"]
[Annotator "ChessAdmin/Komodo Dragon"]
[PlyCount "73"]
[EventDate "2017.??.??"]
1. c4 Nf6 2. Nc3 e6 3. Nf3 {now Black could just as easily go into a
Nimzo-English hybrid with ...Bb4, but it seems most often a QGD formation is
set up from here.} d5 4. e3 {White has committed to central play and there is
no longer a potential gambit situation on the queenside, now that the c4 pawn
is protected.} a6 {the move actually scores pretty well, leaving Black around
50 percent in the database, but it seems a little slow, given White's
flexibility here.} 5. b3 {by far the most played. White develops his
dark-square bishop and protects c4 again, allowing him to choose to retake
with a pawn in case of an exchange and exert more control over d5.} Bd6 {
a good square for the bishop, also signaling that Black will look to use his
control of e5 strategically.} (5... c5 {is the usual reaction by Black. Here's
an instructive and tactically fierce game featuring GM Mamedyarov as an
example:} 6. Bb2 Nc6 7. cxd5 exd5 8. Rc1 Bg4 9. h3 Bh5 10. Na4 Nd7 11. Be2 b5
12. Nc3 Nf6 13. O-O Be7 14. a4 Bxf3 15. Bxf3 Rb8 16. axb5 axb5 17. Ne2 Qd6 18.
Nf4 Nb4 19. Ba3 Na6 20. d4 b4 21. Bb2 O-O 22. Bxd5 Nxd5 23. dxc5 Nxc5 24. Nxd5
Rfd8 25. Qg4 Bf8 26. Nf6+ Kh8 27. Qf5 g6 28. Ne4+ {1-0 (28) Mamedyarov,S (2801)
-Georgiadis,N (2526) Biel 2018}) 6. Bb2 O-O 7. g4 $5 {this was a novelty in
tournament play, although it has been tried several times since with good
results. The idea of sacrificing the g-pawn to open the file in this manner is
a theme encountered in other openings.} Nxg4 {Black chooses to accept the
challenge head-on.} (7... dxc4 {is an alternative.} 8. g5 Nfd7 9. Bxc4 $11) (
7... c6 $5 {is suggested by Komodo Dragon as another way to decline the pawn.
The point is to reinforce d5 while supporting a potential ...b5 pawn thrust.})
8. Rg1 f5 {Black maintains the knight outpost, at least temporarily, while
still allowing for ...Nf6 in the future. It also opens the 7th rank to lateral
defense. However, it leaves the kingside a little loose and weakens e6, a fact
which White later exploits.} 9. cxd5 e5 {Anand has given the pawn back
immediately, but now maintains the advanced e5/f5 pawn duo.} 10. h3 Nf6 11. Ng5
{even with material equality, White needs to play actively to justify his
uncastled king and isolated h-pawn. The knight gets into the game - not being
very effective on f3 - by eyeing e6 and also clearing the diagonal for the
queen.} Qe7 {covering e6 and g7.} (11... h6 $2 {this might be the obvious move
played at the club level, in order to kick the knight. Let's see what would
happen.} 12. Ne6 Bxe6 13. dxe6 {while at first glance White's pawn looks weak,
Black has no immediate way of dealing with it and his own f-pawn has similar
problems.} Nc6 14. Qf3 {and White has threats of Bc4 and Qg2 coming up, along
with queenside castling as a possibility.}) 12. Qf3 {this allows the queen to
move to the g-file, pressures f5, and also places it on the long diagonal.
This last point is shortly used to good effect.} (12. Ne6 {the engines agree
that this is best played immediately.} Bxe6 13. dxe6 {and the pawn is
temporarily immune from capture due to the Bc4 skewer tactic. White can then
follow up with Qf3.}) 12... Kh8 (12... e4 $5 13. Qg2 Nbd7 14. Ne6 Rf7 15. O-O-O
$14) 13. Ne6 Bxe6 {now b7 is undefended.} (13... Rg8 {is the engines'
preference. Again, leaving the strong Ne6 in place looks counterintuitive, but
White still does well from the exchange.}) 14. dxe6 Qxe6 15. Qxb7 {White now
has the bishop pair and his pawn structure overall is no worse than Black's.}
Nbd7 16. Bc4 {a logical move, but hitting the queen is of limited utility for
White here.} (16. Bxa6 {pawn snatching may be possible, but Black should get
some compensation in terms of the half-open a-file and a strong center, while
White's king starts looking a bit vulnerable.} e4) (16. O-O-O) (16. Qc6) 16...
Qe7 17. Qg2 Nb6 $11 {White has no more immediate threats to make and Black has
equalized. White will need to do some maneuvering to start playing dynamically
again.} 18. Be2 a5 {looking to break up White's pawns and make inroads on the
queenside.} 19. Bb5 {a good example of prophylaxis. It feels a bit strange to
move this bishop yet again, but it is the best way to prevent ...a4.} Rad8 20.
Qg5 {prompting Black to respond with} g6 {and now} 21. Qh6 {prompts} Ng8 22.
Qg5 {White would be fine with an exchange here, so Black returns the knight.}
Nf6 (22... Qxg5 23. Rxg5 {and now White's king position is much improved,
lacking a queen to threaten it, and with two bishops and the half-open c-file
to play with.}) 23. Rd1 {at this point queenside castling would not seem to be
an improvement for White's king, so the center is reinforced.} e4 {this
logical-looking move causes Black a few headaches, after White's next. The
long diagonal is opened and Black loses control of d4 and f4, although gaining
space.} (23... Qe6 {maintains Black's grip in the center.}) 24. Qh6 {pinning
the h-pawn and threatening Rxg6.} Rg8 25. Ne2 {Black now immediately moves to
contest the open long diagonal.} Be5 26. Bxe5 Qxe5 27. Nf4 $1 {the key move to
give White the initiative. The Bb5 is hanging, but White has counterplay on
the kingside if that happens.} g5 {an excellent defensive pawn sacrifice by
Anand, echoing Nepo's original one.} (27... Qxb5 28. Nxg6+ Rxg6 29. Rxg6 Rg8
30. Rxg8+ Nxg8 31. Qe6 $14) 28. Rxg5 Rxg5 29. Qxg5 Rg8 30. Qh6 {the position
is still tricky here and perhaps Anand was under time pressure, as his next
move effectively loses.} Rg7 $2 {this looks like a solid defensive move, but
in fact it leaves White's queen too active.} (30... Rg1+ 31. Bf1 Nbd7 32. Ne2
Rg6 {and Black should be fine, his space advantage and piece activity
compensating for the pawn deficit.}) 31. Bc4 {a subtle move that even looks
positionally wrong at first, trading off White's good bishop.} Nxc4 (31... Nfd5
{is the engines' recommendation, but White retains an endgame advantage after}
32. Ke2 Nxf4+ 33. Qxf4 Qxf4 34. exf4 Nxc4 35. bxc4 $18 {as Black can do
nothing about White's plan of Rb1-b5, for example} a4 36. Rb1 Rg6 37. Rb5 Rc6
38. Rxf5 Rxc4 39. Rg5 {with what should be a winning rook endgame, as White
can transfer his rook back via g3.}) 32. bxc4 {the b-pawn finally fulfills its
destiny. From a strategic perspective, the opening of the b-file is also
potentially very good for White, if he can get the rook on it.} Qb2 {Black
looks to get his pawn back, but has to keep defending the Nf6.} (32... Qd6 {
does not help much either, as after Ne2 and Rb1 White is taking over the game.}
33. Ne2) 33. Ke2 {White now has no real weaknesses and his pieces are in a
much better position to go after Black's king.} (33. Ne2 {also works,
protecting g1.}) 33... a4 34. Ne6 {White goes back to the weak e6 square, this
time unchallenged.} Rf7 35. Nf4 {this is sufficient to win without the
complications of attempting a direct attack.} (35. Nd8 Rg7 36. Rg1 $6 {allows
Black to keep fighting} (36. a3 {as in the game}) 36... Ng4 37. hxg4 Qa3) 35...
Rg7 36. a3 {physically blocks Black's ...a3 and is untouchable, due to the
hanging Nf6. Essentially Black has no good moves at this point.} Ne8 {Black
tries to cover everything, but is not successful.} (36... Qb6 {is the engines'
best try} 37. d3 Qb2+ 38. Rd2 Qc3 39. Ne6 $18) 37. Qc6 {forking the Ne8 and
the a4 pawn, so after the next move White will be up two pawns, one of which
is the passed a-pawn, with no compensation for Black.} 1-0