Serena Williams may have blown away Maria Sharapova on Centre Court to reach the final, but she admits it was her battling comeback victory against Heather Watson that helped prime her for the challenge of pursuing a sixth Wimbledon title.
The world No.1 was 3-0 down in the final set of her third-round match against Watson last week, before rallying to break British hearts by winning 6-2, 4-6, 7-5 in two hours and 14 minutes.
Serena also recovered from a set down to beat Victoria Azarenka in the quarterfinals before seeing off Sharapova 6-2, 6-4 on Thursday, to improve her dominant head-to-head record against the Russian to 18-2.
Victory over Garbine Muguruza in Saturday's final would see her hold all four major singles titles, as well as move closer to becoming the first woman since Steffi Graf in 1988 to complete a calendar Grand Slam.
Asked about her displays against Watson and Azarenka, she said: "I think sometimes you definitely need them [matches like that] or you're not feeling your game, or you feel like you're not necessarily playing your best tennis.
"You need them. I think sometimes they're important to know that, 'Okay, I can last two hours, I can last two and a half hours if I need to.
"Just mentally it's like, 'Okay, I know I can do that. Sometimes they're important.
"Pretty much everyone, like I always say, would prefer to have an easier match. But, you know, when you have a tough match and you're able to come through, obviously that really helps."
Watson had been two points away from beating Serena when she served for the match at 5-4, and took heart from pushing the world No.1 all the way.
"I gave myself the opportunity to play against the best player in the world. I also gave myself the opportunity to beat her," Watson had said. "I didn't take it this time. But I'm really glad I was in that situation because I can learn from it and do better next time.
"I've learnt that I can compete with the best in the world and play really good tennis. And, yeah, it's a positive. I just need to use this to motivate myself for the future and know that I can be there, I can compete, and I can be at the top of the game."