By the 73rd-minute mark, both teams were rolling players off the bench to counter the heat.
However, two minutes later Saiko claimed a brace, pouncing on a scramble in the penalty box to extend the lead to 3-0 and compound the heat on Bay United.
Ahinga Selemani pulled one back, 3-1, after the ball was worked down the right flank and turned in to the left upright for the Bay United striker to boost his premiership tally to eight but his team are still struggling to break their goal drought.
Greatholder said the Fox Slotemaker-skippered Tasman "arguably" deserved to win the match after exploiting areas on offence and protecting ones on defence.
English import Vickers and speedy Jesse Randall, a Kiwi under-17 world cup rep, made life difficult for Bay United, especially the former who was strong on the ball and marshalled the back line well, he said.
"We didn't have any hard-luck stories today because we haven't fought well and the opposition has so deserved to win the game," said Greatholder, emphasising it wasn't like previous encounters where Bay United had created opportunities but couldn't put the ball into the net.
While seventh-placed Bay United's confidence had taken a hit with their inability to score, he said some soul searching was required to turn their fortunes around as they host bottom placed Canterbury United Dragons in Napier on Sunday.