The conversion made it 10-0, which soon became 15-0 when winger Cameron Jeffries scored after the Mount failed to disarm a bomb inside their own half.
That setback sparked the home side into action, with Sam Gavigan and Chris Elvin particularly effective before Troy Elvin scored in the corner courtesy of some fine handling and distribution in the midfield.
An early Mount penalty goal in the second half closed the margin to 15-8, but that is as close as it got thanks to Morris' reliable boot.
He slotted two penalties to extend the advantage to 21-8, before Josh Hall scythed through the Mount defence to put the rapid Nick Thomson in to score.
Morris, who is gradually making a name for himself as a runner rather than solely as a fine kicker and distributor, duly converted to ensure another win for the runaway competition leaders.
A late Mount try to David Smart was thus rendered as consolation, with other results around the Bay not exactly making the home side feel any better about their weekend's work after a typically bruising battle of the bridge.
Elsewhere, wins to Rotoiti and Opotiki set up the next month perfectly for near knock-out rugby.
Rotoiti rode two tries from Jesse Acton and the steady boot of Willie Ripia to steal four crucial competition points away from Te Puke Sports at Murray Salt Stadium.
The defending champions normally go up a level when playing at home, but the shock loss makes what looked to be a likely home semifinal far less certain.
Opotiki ran away from Whakarewarewa in the second half to post an emphatic 38-8 scoreline that catapults them right back into the semifinal frame.
Te Hata Wilbore scored a treble in the six-tries-to-one romp that leaves Opotiki tied on 30 competition points with Rotoiti - just one win outside the top four.
The two teams at the other end of the table had contrasting fortunes despite both registering losses. Paroa were gallant but came up just short of receiving a bonus point in falling to Te Puna 29-21.
Rangataua managed to grab themselves a point to pull alongside Paroa for a share of ninth place on the ladder after their close 17-13 loss to Greerton Marist.
Te Puna's win, and Mount's loss, puts Te Puna into outright fourth place on the ladder, and with a comparatively easy draw for the rest of the round robin the men of Maramatanga Park must suddenly be fancying their chances.
Points ladder: Tauranga Sports 62, Te Puke Sports 44, Greerton Marist 39, Te Puna 34, Mount Maunganui 33, Rotoiti 30, Opotiki 30, Whakarewarewa 26, Paroa 13, Rangataua 13.
Division One
Te Teko beat Rangiuru 17-15, Poroporo beat Ngongotaha 20-17, Kahukura beat Whakatane Marist 28-15, Ruatoki beat Marist St Michaels 25-21, Waikite beat Katikati 36-7.
Points table:
Te Teko 17 Rangiuru 15, Poroporo 20 Ngongotaha 17, Kahukura 28 Whakatane Marist 15, Ruatoki 25 Marist St Michael's 21, Waikite 36 Katikati 7.
