You played right into the sanrensai strategy, letting him get two walls and the two-space jump at G10.

Letting him resolve both corners early is aji keshi, and makes his game much easier.
You have to play lighter and more flexibly, maintaining aji.
(;GM[1]FF[4]CA[UTF-8]AP[Quarry:0.2.0]SZ[19]GN[Round 2]KM[7.0]PB[A.N. Other 16, 3kyu]PW[thirdfogie, 4kyu];B[dp];W[pd];B[dd];W[pq];B[dj]C[I can't remember if I ever faced a sanrensei before. There was no time to order and read Michael Redmond's book, so I just had to make it up as I went along.
JB: Even with no experience, you can see that he is betting on influence. So you know that you will be attacked as soon as you play a stone anywhere near that side. If you defend competently, his attacks will not result in a kill, so you know that he will then try to make territory while attacking.
];W[fc]C[JB: A fine anti-sanrensai play.];B[hc];W[cc];B[cd];W[dc];B[ed];W[fb];B[ge];W[fq];B[fo](;W[cq]C[JB: This is playing right into his plans. You are encouraging him to attack you and make another wall. With the northern wall in place and D10, this works too well for him. See variation.];B[cp];W[dq];B[ho](;W[ep]C[JB: This just helps him build his wall. See variation.];B[eo];W[iq]C[I considered playing at a, but I would then expect Black to play at b, which would be like pushing from behind, only at twice the size. The move played did not turn out well either.]LB[jo:b][hq:a];B[gq];W[gr];B[fp];W[eq];B[hq];W[hr];B[bq](;W[po];B[bc];W[bb];B[bd];W[ab];B[gj]C[The game was lost!
JB: I halfway agree. But this is no time to panic. See variation.]LB[do:a](;W[do]C[JB: This is premature. Save the aji. See variation.](;B[co]C[I expected Black to play the other atari, see variation.](;W[cl]C[Maybe this? The idea is to play next at a or b.
JB: You don't have room for this. An approach move like this assumes that you are willing to build on your stone. It suggests that you do not want a quick fight. Whereas, if fact, you do. See variation.]LB[bj:b][dn:a];B[bj]C[After this move, I was committed to saving the marked white stones, but the prospects were not good. The only way was first to threaten to capture the marked black stones,]SQ[cl][do]TR[co:cp][dp][bq];W[dn];B[cn];W[dm];B[el]C[I did not expect this move.];W[br];B[cm]C[I expected Black to play at a rather than as shown.]LB[bl:a];W[dl];B[bl];W[bk];B[bm];W[cj];B[ak];W[ck];B[bi]C[This fight will decide the game. It still looked bad for White.];W[ci];B[ch];W[dh];B[cg](;W[di]C[JB: You have committed yourself. So play the most aggressive moves that you can. See variations.];B[ej]C[JB: At this point it looks bad. Black has patched his last weakness.
END COMMENTS];W[gh];B[fh]C[I expected Black to play at a to seal in and capture the white stones..]LB[hh:a];W[fg];B[eh];W[dg];B[cf]C[I would have played at a. Black was taking a long time for each move and playing very carefully.]LB[eg:a];W[eg];B[gg];W[gf];B[hg];W[fe];B[fd];W[hf];B[ig];W[ie]C[The White stones have escaped, but it looks like Black will get territory in the centre now.];B[hd];W[kd];B[kg];W[pi]C[I knew this move risked a black move at a, but thought I had to play it in order to compete on territory.]LB[je:a];B[je]C[As expected. I planned to push down ahead of Black, and then use the peep at a to fix everything.]LB[gc:a];W[id];B[jd];W[gc];B[he];W[if];B[ic];W[jf];B[kf];W[jc];B[ke];W[gd]C[I had not planned this semeai. At first glance, it looked good for White. But I had not noticed that the big white group will soon have only 6 liberties.];B[ff];W[ef];B[jg];W[ff]C[I was still not worried.];B[jb];W[kc];B[kb](;W[hb];B[ib](;W[lb]C[This move obviously fails. My opponent had only 2 minutes left on his clock, whereas I still had 15. Yet I was the one who impatiently stopped reading. I was bored with defending the eyeless white group, and wanted a quick resolution. This impatience is a recurring fault of mine.The variations show some attempts to keep fighting, none of which occurred to me during the game. The variation starting with white a followed by white b looks like White's best hope. Leaving the fight at the top unresolved with the threat of returning there if the big white group ever got more liberties is a new theme for me.]LB[mc:a][fj:b];B[lc];W[ld];B[mc];W[mb];B[md]C[White resigned.])(;W[mc];B[lb]C[Both marked groups now have 6 liberties.]TR[ib:lb][hc:id][fe:ie][ef:jf][dg:fg][dh][ci:di][cj][bk:ck][cl:dl][dm:do](;W[nd];B[ha];W[gb];B[ec];W[eb];B[db];W[cb];B[ei];W[lc];B[em];W[mb];B[en];W[la];B[dk];W[ka];B[df];W[ja];B[ee]C[Black wins.])(;W[lc];B[mb];W[nb];B[nc]C[Black wins])(;W[fj]C[I should have tried this move to get more liberties, or escape in a new direction. If White can capture the marked black stones, the game can continue, and Black would be very short of time. I was not alert enough to think this way during play.]TR[ib:lb][hc:ic][hd][ge:he];B[gi];W[ek]C[M](;B[fk];W[dk];B[fi];W[fm](;B[em];W[en]C[M](;B[fn];W[fl];B[gl];W[gm];B[hm];W[hl];B[gk];W[hn];B[im];W[gn];B[hp];W[go];B[gp];W[io]C[Black cannot allow this. He now has to save his marked stones, so his centre territory will vanish.]TR[ib:lb][hc:ic][hd][ge:he])(;B[fl];W[fn];B[go];W[hn];B[io];W[hm];B[gn];W[gm];B[lc];W[kn]C[??]))(;B[gm];W[gn](;B[fn];W[fl];B[hn];W[gl];B[hm];W[hk])(;B[hn](;W[go])(;W[gl];B[fl];W[fn];B[go];W[hm];B[en];W[em];B[im];W[gk];B[fj];W[il]C[Ok for White?]))))(;B[fl];W[fi];B[hh];W[fk];B[gk];W[ei];B[df]C[Black probably still wins the semeai.])(;B[em];W[gk];B[ei];W[dk];B[fi];W[fk];B[hk];W[en];B[fn];W[fm];B[gm];W[fl];B[gl];W[hj])))(;W[lc];B[lb];W[mc];B[mb](;W[nb];B[nc];W[nd];B[oc];W[ob];B[md]C[Black wins.])(;W[nc];B[ei]C[Black wins.])))(;W[ib];B[hb](;W[ia];B[ld]C[A ladder. Black wins.])(;W[lb];B[lc];W[ld](;B[mc];W[mb];B[md];W[le];B[mf])(;B[ia];W[ka];B[mc];W[mb];B[nb];W[nc];B[md];W[le];B[nd];W[oc];B[mf]C[A geta. Black wins.]))))(;W[ej])(;W[fn];B[en];W[em](;B[fm];W[fl])(;B[di];W[go])(;B[gn];W[fm];B[di];W[fl];B[ek];W[hl])))(;W[cj]C[JB: Provoke a small quick fight in which you can live on one side or the other, or run out.]))(;B[dn];W[co];B[bp](;W[bo];B[bn]C[The white stones are captured.])(;W[cn];B[cm];W[dm];B[bn];W[en];B[bo];W[dn];B[cl]C[This does not look good for White either.])))(;W[cj]C[JB: Make him worry about how he is going to play so that you cannot exploit any cutting points]TR[fd][do]))(;W[fj]C[JB: A fighting move that keeps you in the game])(;W[br]C[JB: How many points is this worth? If he replies, you still can play the cap at F10. If he doesn't, this is about 20 points, IIRC.]))(;W[fj]))(;W[cn]C[JB: Stay light and flexible. Make him worry about his keima.]))