Ireland 56 for 3 beat Afghanistan 95 for 5 (Ghani 44*, Adair 3-16) by seven wickets (DLS method)
Dockrell hit the decisive run as the home side clinched a 3-2 win by seven wickets after reaching a reduced target of 56 with two balls of their seven allotted overs to spare.
When Adair had Ibrahim Zadran caught by Barry McCarthy, he had 3 for 16 and the tourists had been reduced to 26 for 3 inside four overs.
Paul Stirling needed just five runs to reach 3000 in T20Is as Ireland’s reply got under way, and he made it within three balls, cutting Naveen ul Haq for four off the first and taking a single from the third.
Fellow opener Andrew Balbirnie was trapped in front for 9 attempting to sweep Mujeeb Ur Rahman with the score on 17, Mujeeb had Stirling caught at deep midwicket for 16 to give his side hope, and Tucker soon followed for 14.
However, Harry Tector and Dockrell saw their side home for the loss of three wickets.