Anyone who loses three Grand Slam finals in a row, as Serena Williams has done, is going to have some scar tissue. But, going into Saturday's conclusion to the US Open, which will be her fourth attempt to win a record-equalling 24th Grand Slam singles title, her mind looks totally focused on the task in hand, and not on that trio of defeats. 

She has been all business at Flushing Meadows this fortnight. Serena is looking fresh, sharp and healthy - there is a calmness about her here in New York which makes her the strong favourite to beat Bianca Andreescu, a Canadian teenager who will be playing in her first major final.

So far this tournament, Serena's game has been humming like a finely tuned engine, and if the American plays her best tennis, I can't see Andreescu winning. Perhaps Serena struck the ball a little harder in the past, but it was more hit and miss back then.

She's now looking more solid. It's controled hitting now - she only pulls the trigger when she's absolutely ready to go. Even though she's still hitting the ball hard, she is looking for her spots more, and maybe the rallies are one or two shots longer. Playing safely means fewer errors and more winners.

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Without a doubt, Serena is playing at a higher level than she did at this summer's Wimbledon, where she was the runner-up to Simona Halep. 

Twenty years after Serena won her first Grand Slam title at the 1999 US Open, and just days before she turns 38, I think she is playing some of the best tennis of her career because she knows what to do on the court.

If she has lost anything with age, she has more than made up for it by constantly adding to her knowledge of the sport. And she has also improved her technique.

In my view, she is moving as well as ever. She might not be as fast as she once was, but her footwork, her technique, is better and she's still explosive. Cleaning up her technique - I can also really notice the improvement in her forehand - has helped to cut out the unforced errors. That serve has always been there - that's been the mainstay that she has built her game around. 

If Andreescu is to have a chance, she needs to make Serena move, so Serena can't get set for her shots: that would draw some errors. In short, she needs to make Serena run.

Andreescu has the shots to stop Serena from playing her best tennis, as she mixes things up. She's got good speed, she can handle the pace and she moves well. She can also generate her own pace, and she uses her variety very well. She's going to have to play her best ever tennis.

If Andreescu can do that, and if things aren't going Serena's way, perhaps Serena will find herself thinking back to her defeats in her last three major finals: at Wimbledon and the US Open last season and then again at Wimbledon this year.

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But, to my mind, everything is pointing towards Serena winning this final, for what would be her first Grand Slam title since the 2017 Australian Open. 

The fact Serena won her first US Open title at the age of 17 (before Andreescu was born), and is now into another final at the age of 37, tells you how great she is. Her longevity, combined with her excellence, is off the charts.

Playing in front of a home crowd has definitely been helpful to her in the past. It's not that she needs any extra motivation, but it makes you feel good about how you play. Emotionally, New York has been special to Serena for obvious reasons. Equalling the record in America, in front of a home crowd, would be pretty sweet. 

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