Sneaky Move - A Challenging Chess Puzzle

Do you ever get into a position where you know you have a winning tactic, but you have to play very precisely to finish the game? I get into those positions a lot and I think I lose almost every single one of those games. This position that I got in a recent blitz game is a perfect example.                                                                                                                                                             

                                                                                                                                                             

With both the bishop on e3 hanging and the threat of Bd3, pinning the rook to the king, I knew there had to be something in the position that would win me the game. However, there are also some issues with black's position, namely the hanging rook and the weak bank rank.                                                 

I didn't see a clear solution and this was a 3 minute blitz game, leaving me with no time to calculate (though I highly doubt I would have seen the correct move anyway), so I went for Qb1+. The game ultimately ended with me losing on time in a drawn opposite color bishop endgame.                                                                                                                                                                                   

Generally, I think the worst feeling in the world when it comes to chess is losing a winning game where you know right after the game that you missed something. However, the tactic in this position was so inconspicuous that I'm not bothered at all. See if you can find the wild move that I missed, winning the game for black. If you find this sequence, you have a very good tactical eye.                                                                                   

Whether you got the tactic or not, I hope you learn from this puzzle that some tactics are not in the form of a check or capture. Sometimes, a defensive move is the best attacking move and can be the move that finishes off your opponent.