Durban - A calculated century from Vaughn van Jaarsveld laid the foundation for the Dolphins to secure a comfortable 26-run victory over the Titans and secure a home play-off following their One Day Cup win at Kingsmead, in Durban, on Sunday.
The left-hander anchored the innings for the hosts with his 101 off 118 deliveries to help the hosts post 261 all out.
Theunis de Bruyn (81 off 111 balls) and Dean Elgar (59 off 78) then shared a 164-run partnership to give the visitors hope, but Andile Phehlukwayo's career-best four for 49 restricted them to 235 for eight.
That was enough for the Dolphins to end second on the table ahead of the Titans, who they face at the same venue in what is effectively a semi-final on Tuesday, with the Cape Cobras awaiting the winner for Friday's final in Cape Town.
The Titans won the toss and fully vindicated their decision to bowl first under bright sunshine on the east coast.
They were also aided by some poor batting as the hosts lost four wickets in just over 15 overs.
Morne van Wyk was bowled in the first over for a third-ball duck as he played across the line to JP de Villiers (four for 51), who also took out Cameron Delport (10) hopelessly skewing a length ball to Theunis de Bruyn at point.
The 50 was up in the eighth over before Cody Chetty (four) was sent De Villiers straight to David Wiese at short cover.
When Khaya Zondo (15) edged Rowan Richards to wicketkeeper Mangaliso Mosehle, the Dolphins had slipped to 78/4 in 15.2 overs.
Van Jaarsveld, dropped at slip on eight, was holding the hosts together at the other end and went to 50 in 65 balls.
Along with Kyle Nipper (31), the pair put on 72 for the fifth wicket.
However, Nipper top-edged a slog sweep off Henry Davids to Qaasim Adams, with Phehlukwayo (one) becoming Elgar's (three for 43) first wicket six runs later.
Calvin Savage (43) added 68 with Van Jaarsveld to further aid the home side with the latter reaching his seventh one-day career ton in 116 balls.
He eventually fell with the total on 224, with the tail folding relatively easily to leave the Dolphins all out in 49.4 overs.
The Titans were in little hurry to get going when they began their chase and their cautious approach also lead to two early wickets.
Jacques Rudolph and Henry Davids both made seven, falling to Tshepo Moreki and Phehlukwayo as the Pretoria side slipped to 14 for two.
Then came the massive De Bruyn-Elgar partnership, which began sedately and eventually blossomed into a potentially match-winning position.
The pair batted for 30.2 overs at a rate of 4.94 deliveries, taking the total to 164 for two -- with 98 needed in 69 balls.
But De Bruyn's miscued scoop-sweep off Phehlukwayo was caught by Daryn Dupavillon.
That was the start of a spell that saw four wickets for five runs. Elgar was among them leaving the Titans in a hole on 169/6.
David Wiese (50 off 38) tried to rescue them, but ultimately fell short handing the hosts victory.