xela: Black is ahead six liberties to four... at first sight it seems impossible for white to win.
xela: After , I don't see any way for black to stop white from connecting out. The stones can easily end up short of liberties.
xela: was the move I had trouble finding (and even now I'm not totally convinced it works). If then white wins the race.
xela: This variation shows the shortage of liberties: black can't play a. If black tries other responses instead of , I think similar things happen (but there are many variations... I'm sure unkx80 will soon point out one that I've missed!)