After the stand was broken by Josh Dwight (2-32 from 9.3 overs) St Peters were bowled out for 125 in the 40th over. Myles Timoti finished with excellent figures of 4-19 from his 10 overs.
In reply, Tauranga Boys College had a steady start, losing their first wicket at 32 in the 15th over.
However, from a relatively strong position of 61-2 the wheels began to wobble, with Tauranga Boys losing a steady stream of wickets to St Peters' spin attack. Alex Lunn was the pick of the St Peters bowlers, picking up 5-19 from 10 overs and was well supported by Whitley's 2-25.
Tauranga Boys were deep trouble at 94-8 when Myles Timoti joined his brother Elliot at the crease.
Adding to his good bowling bowling performance, and a fine day for the Timoti family overall, Myles formed a definitive partnership with his sibling, taking Tauranga Boys College to the brink of victory.
With two runs needed for the win, St Peters delivered up a no-ball to tie the scores. But in a final twist, Myles was run out on the no-ball, leaving No 11 batsman Henry Conway to join Elliot Timoti with a solitary run needed for the win.
Displaying the nerves and patience he had shown all innings, Elliot Timoti hit the winning run in the next over, finishing with a superb unbeaten match-winning innings of 55.
Gillette Cup semifinal scores: St Peters Cambridge 125 from 39.3 overs (Ben Schilt 35, Jono Whitley 26no; Myles Timoti 4/19, Josh Dwight 2/32) lost to Tauranga Boys College: 126/9 (47.3 overs). Elliot Timoti 55 not out. Tom MacRury 20. Alex Lunn 5/19. Jono Whitley 2/25.