(;SZ[19]EV[London Open]RO[3]PC[London]PB[Robin Upton]BR[1 Dan]PW[Olaf Lorenz]WR[1 Dan]KM[6½];B[pd];W[dp];B[dd];W[pp];B[jd];W[qf];B[nd];W[rd];B[qc];W[qi];B[cn];W[fp];B[dj];W[fc];B[ec];W[fd];B[df];W[cc]C[Too early.];B[dc];W[bd];B[cb];W[bb];B[cd];W[bc];B[db];W[bf];B[cf];W[be];B[bg];W[ba];B[hc];W[ff];B[jj]C[Black had used 18 minutes, white had used 9 minutes at this point.];W[fh];B[fj];W[ig];B[kg];W[ii];B[ij];W[kh](;B[nq];W[np];B[oq];W[pq];B[mp];W[no];B[jq];W[pl];B[cq];W[cp];B[bp];W[dq];B[br];W[cr];B[bq];W[hq]C[Black had used 36 minutes, white had used 18 minutes at this point.];B[en];W[ho](;B[ir]L[hm]C[Not a very interesting move. This would be better at 'a'.];W[mo];B[lp];W[kn];B[oi];W[ng];B[lh];W[ki];B[nh];W[lg];B[mg];W[lf];B[mf];W[ke];B[le];W[kf];B[ld];W[li];B[mh];W[hi];B[hj];W[gb];B[hb];W[rc];B[ge];W[fe];B[nl];W[om]L[pj]C[This should be at 'a'.];B[qj];W[pj];B[qh];W[pi];B[ph];W[ri];B[rh];W[qb];B[pb];W[qd];B[pc];W[qa];B[pa];W[sb];B[pf]L[pr]C[This is not that big. Playing at 'a' is much bigger.];W[ei];B[di];W[ej];B[ek];W[fk];B[el];W[gk];B[hl];W[fm];B[fl];W[gl];B[gm];W[gj];B[gn];W[hm];B[hn];W[im];B[in];W[jm](;B[gr]C[The previous variation shows a much more sensible option for black, who should keep the game simple since he is a ahead. Black had used 68 minutes, white had used 40 minutes at this point.]N[Aggressive];W[io];B[jo]L[go]C[This should be at 'a'.];W[jn];B[go];W[dm];B[em];W[hr];B[gq];W[gp];B[hs];W[er];B[gs];W[ds];B[fs];W[fq];B[es];W[dn];B[co];W[do];B[bl];W[cl];B[bm];W[dk]M[ek][el][fl][em][en][gn][gm][go][hn][in]C[Black resigns.])(;B[jn]L[km]C[Black should take K6 now, and see how white responds to the threat of following up at 'a'.]N[Simple]))(;B[hm]C[This is a more profitable way to exert gentle pressaure on the white stones. Black is gaining in strength all the time.]))(;B[jh]C[Black should use his strength in this area. Cut!]N[Strong];W[ji];B[ki];W[lh];B[hi];W[ih];B[jg]M[ki]C[White cannot capture the marked stone, so starting this fight is an ideal use of black's strength.];W[kj];B[li]))