The North Otago cricketer and his Wellington Firebirds team-mates were crowned Plunket Shield champions last week.
They were in first place heading into the final round of games.
The only team capable of overtaking them on the ladder was their opponents, Northern Districts, setting up a pseudo final in Hamilton.
The match was evenly poised after three days with Wellington leading by 88 runs.
Smith was instrumental with the ball, taking three for 57 in the second innings.
With the final day being washed out, a draw coupled with first-innings bonus points was enough for Wellington to lift the shield.
It was the first title for Smith in his professional career.
Speaking to the Oamaru Mail last month, he said: "If I could retire and only win one, the Plunket Shield would be the one I want to win."
He also led the competition with 33 wickets at an average of 17.18.
The celebrations were shortlived, Smith jumping on a plane to England on Sunday.
He begins his stint as an overseas player for Worcestershire tonight (NZT).
