Tristan Doubles Thru Me

Cliff raised to 2K in late position and Tristan moved all-in for 3.3K total. I then reraised all-in for 9.4K. Cliff folded and I was behind with AQ to Tristan's AK. The flop came 6-7-9 all clubs and I held the ace of clubs. I picked up even more outs when the six paired on the turn, but a king on the river gave Tristan the pot and the double up.