James Harden was picking and rolling his way through the Mavericks defense in the 4th quarter, working to bring his team back from a double-digit deficit. Dallas was desperate to stem the Thunder tide and to do so would mean keeping Harden from driving on their perimeter defense repeatedly. If they could slow down Harden, Dallas had Kevin Durant and Russell Westbrook under control and could send the series back to OKC.
James Harden decided to put an end to that notion with this slam.
Even though OKC still trailed at that point and would need a few more possessions to take the lead, this was the play that convinced me that the Thunder would win.