Friends know each other inside and out, and in the semifinal, it was about bringing out new parts of the game to gain an advantage.
Olympic Games second-place finisher Truls Möregårdh succeeded in doing just that initially and won the first set relatively easily.
Then the semifinal shifted.
Anton Källberg turned a deficit into a victory in the second – and then it was the 27-year-old's show.
I started dominating, then I found another way, another tactic that made it difficult for him to attack as easily as he did in the beginning. It changed a lot, says Källberg in the victory interview on Youtube.
"Maintaining the tactic"
He delivered several point-winning backhand shots, which both surprised and made Möregårdh, 22, gesture in despair. In the fourth, he also made a rare shot, where Källberg gripped the racket with both hands and swung over a double-fisted backhand.
I wanted to play more on backhand, where I felt I was better than him, and I managed to maintain that tactic.
Anton Källberg did lose the fifth set, but had no trouble securing the victory in the next.
He earned six match points. Möregårdh saved one, and Källberg took a timeout to gather his thoughts.
Which he succeeded in doing.
Tough final
Shortly after, he won the ball that was needed to celebrate; partly over the victory against his friend, partly over being the first Swede to reach the final in a WTT Champions tournament, the highest level on the world tour.
In the final at 3:00 pm on Sunday, he will face Chinese player Lin Shidong.
It's going to be super tough. He has won a few recently and knows how to win tournaments. He seems to be in good form, says Källberg.
Corrected: An earlier version had incorrect information about the historic nature of Källberg's final spot. The correct information is that it is the first time a Swede reaches the final in a WTT Champions tournament.
