Tactics in the closed Spanish

Introduction

I hadn't played a classical game for almost a year. After studying abroad for a few months, I finally got to go back to my local chess club.
The first event I got to play was a rapid tournament, where I scored a decent 4/6. My preference, though, has always been for classical.

Luckily, the next event would be our open tournament: seven games, one game per week, game in 100+10. I had only played in four rounds last year, and I was determined to fight until the end this time around.
Besides, I joined the club when I was 15 and have improved a lot since, so I have kind of an obligation to win this thing at some point.

The game

For the first round, I knew the Swiss system would give me a weaker opponent, so my plan was to play solid and win without too much risk.
That meant putting my beloved King's Gambit on the back burner in favour of a more measured approach: hence my decision to play the Spanish (Ruy Lopez, for those outside Europe).

So I won rather quickly, with straightforward play. Goal achieved?

Not entirely, since some of the critical moments in this game saw lackluster judgment on my part. At least they make for interesting analysis.

The opening alternative: 6. d4!?

In the Spanish, white usually plays for the move d4. It's so principled that it always deserves attention.
After 5. ...Nf6, though, I wasn't going to spend too much time calculating something like this: I knew that the simple 6. 0-0 would be good, and it aligned with my goal of playing a solid game.
Still, the analysis of the more aggressive move is interesting in its own right.

The best continuation for black, starting with 6. ...d6, is basically a mainline closed Spanish where white hasn't had to play Re1.
That technically leaves white up a tempo, although the plan of Nbd2 followed by Re1 and Nf1 is so natural that white may as well play it regardless.
The extra tempo might be used to play a4 at some point. Still, black should be okay.

It's even better the second time: 7. d4!

After black's slow 6. ...h6, the move d4 should intuitively be more potent than before. This is where I could have dug in to calculate some variations, and my 7. c3 may have been a bit lazy (though, of course, perfectly sound).
The move 7. d4 can of course be played intuitively. I imagined it'd probably work, and the analysis confirms so.

Like before, black has to respond with 7. ...d6, and now white can temporarily win a pawn.
I say temporarily, but it's only with optimal defence that black regains the pawn; and white retains some advantage even in that line. This would definitely have been more testing than my move, but I'm not unhappy with the way I played.

The critical continuation: 12. ...dxe5

I obviously didn't play 11. Bd5 without intending some aggressive follow-up. After 11. ...Bd7 12. dxe5 dxe5, I'd discerned both 13. Bxc6 and 13. Nxe5 as interesting moves.
However, both of these fail. My calculation at this point wasn't terribly precise; I just smelled blood here (misunderestimating the problems caused by my undeveloped queenside), and decided not to double-check until the next move.

So both my candidate moves would have failed! I actually realised before the end of the game that 13. Bxc6 isn't all that, and I like to think I would have correctly assessed 13. Nxe5 too.
Still, after white backpedals with something like 13. Nbd2, it's clear that 11. Bd5 was a bad decision.

A quicker win: 15. e5!

By the time 14. ...Qc7 happened, I had a comfortable advantage. Perhaps that made me complacent, because here I had the decisive 15. e5.
I did consider this move. I'm not sure if it was lazy or imprecise calculation, but for whatever reason the win didn't seem clear to me.

While I ended up winning by a similar tactical idea, this was yet another instance of not putting in the effort to fully navigate the complications. I know I'm usually good enough to find tactics like these, so I know what I need to work on.

Thoughts

I did win without much risk, which is what I intended. For that reason, I'm okay with not playing the aggressive 6. or 7. d4.

What I'm not so much okay with is my sloppy 11. Bd5. Since the variations specifically after 13. Nxe5 get rather complicated, I'm not mad at myself for not calculating everything. However, I should have realised how precarious these complications are with an undeveloped queenside, and gone for simpler play instead.

There's also a lesson in my opponent's response: perhaps he simply miscalculated 12. ...dxe5, but there's at least a chance he trusted my judgment merely because my rating is higher. When you do that, you self-destruct with moves like 12. Rb8 just because you fear complications.

Lastly, while 15. e5 wasn't necessary to win, I feel like I should have played it. I was already considering it, and I can't make sense of how I may have miscalculated such a clear win.

In the end, a point is a point. But my bad calls on moves 11 and 15 serve as a warning, since the next round won't be as easy...

I hope you find some use in these thoughts, or at least some entertainment in the game. Thanks for reading!
~ Lars420