But when Locke crossed for Pontypridd's fourth try, it left the scores tied. Replacement fly half Simon Humberstone had the chance to win it though his difficult conversion went wide meaning the sides shared the spoils.
Earlier on, tries from Garyn Smith and Jake Thomas had given Pontypridd a 7-12 half time lead. Dai Flanagan had added a conversion with Jacobs' 22nd minute score and a Garland conversion Llandovery's response.
The second half saw Garland and Rees cross for Llandovery with the former booting two conversions and two penalties.
Dafydd Lockyer and Locke then got Pontypridd back into it, but in truth, it was a game neither side deserved to lose.
In the early exchanges, Pontypridd had been on top with the Llandovery pack under immense pressure. It was no surprise then when both Greg Cunniffe and Lawrence Reynolds were sin binned in quick succession.
The numerical difference between the two sides showed immediately as Smith arced in for a try which Flanagan converted. Jacobs soon responded though with Garland's conversion levelling the scores.
Flanagan then put a difficult penalty effort wide but his side did go into the interval ahead. After repelling a Llandovery attack, No. 8 Owen Sheppeard sniped off the back of a scrum with Thomas in support to cross for a try wide out.
The second half saw Pontypridd raise the tempo, taking quick tap penalties and driving up to the home line. It failed to make an immediate impact though and with the tension rising, Llandovery moved back into the lead with Garland converting his own score on the hour mark.
Flanagan and Garland then exchanged penalties before Rees regained the initiative for the home side by diving over. Garland added the extra two and kicked a second penalty and with Llandovery 12 points clear with 10 minutes remaining, Pontypridd looked in trouble.
The Sardis Road club are not champions without reason though and as the game reached its climax, they fought back impressively. Lockyer scored Pontypridd's third try, Humberstone converting after replacing Flanagan.
And with the pressure continuing, Locke went over for a close range try leaving Humberstone with a kick from near the touchline to win the match. His attempt went wide though, a fantastic advert for Premiership rugby eventually finishing in a draw.