Whatever you do, don’t mention the “S” word around Serena Williams. You and I may whisper it – “slam”, there we said it – but not within earshot of the world No.1. Not this summer. Not in reference to “Serena” or, worse still, “The Grand”. The “S” word does not exist in her world.

In the Williams household, people in a strop do not slam doors, they merely shut them very loudly. Serena jumping for a high volley, then, is going for a shutting-the-door-very-loudly dunk. Wimbledon, for this year only, is a major championship, a grand and venerable tournament, the most prestigious event in the calendar, but it is not a grand s… oops, we almost said it.

Twice in the past three days, an intrepid news hound has dared mention the “S” word in the post-match press conference and has been put firmly in his place. Miss W does not discuss the “S” word any more. End of story.

The reason for all this walking on eggshells is that Williams is on course for the Grand Slam (winning all four major titles in the course of one calendar year) and the Serena Slam – if she wins on Saturday, she will hold all four big titles (her current US Open title is from 2014). She has not been beaten at a major championship since she was ousted by Alize Cornet in the third round here last summer.

No one has completed the Grand Slam since Steffi Graf in 1988. She rounded off her amazing season by adding the Olympic gold medal in Seoul (so completing the Golden S-word) and no one has come close to doing it since. Well, no one but Serena herself – she completed her first Serena Slam by winning the Australian Open in 2003 to add to the French, Wimbledon and US titles she had won the year before. Total domination at all of the major tournaments is a rare, rare thing.

Unsurprisingly, Williams is keen to relieve a little of the pressure by not thinking about what she might achieve in the coming days and months. She doesn’t want to talk about it, you had better not mention it and shut that door quietly when you leave.

The nerves are still there, though. She has not been at her best, her all-powerful, all-conquering best, in the past eight days. As is her way, she has found her inner champion and managed to raise her game when she has been on the ropes, but it has been anything but easy. Heather Watson came within two points of victory on Friday evening and Victoria Azarenka pushed her to the very limit for a set and a half in the quarter-finals. Williams survived but she had to dig deep and fight as if her life depended upon it to keep her dream alive.

Oddly, Williams is a bit of a pessimist, something that her coach, Patrick Mouratoglou, has been trying to drum out of her. She saw coming so close to losing against Watson as a negative; Mouratoglou has been trying to convince her that almost losing and then finding a way to win is a positive. Maybe if she lifts the trophy on Saturday, he may finally convince her.

Throughout her career, the world No.1 has always been able to find that extra gear, that little edge, when she has needed it. To win her last two major titles, she fought through illness and still somehow managed to find a way to succeed. Coughing, spluttering and, at the French Open, running a temperature, she still proved herself to be unbeatable. But that is her greatest strength: she dares the opposition to beat her and, for the most part, nobody dares.

Azarenka brought the very best out of herself and therefore – and unfortunately for her – from Williams but still could not stop her old rival from thundering into the semi-finals 3-6, 6-2, 6-3. She, like Williams, is warrior and her heavy hitting from the baseline caught the No.1 cold in the first set. Moving up a gear, Williams went toe to toe with the former Australian Open champion until she found a way to break the Azarenka serve in the second set and from there she was in total control.

Now Maria Sharapova stands between Williams and the final, a woman she has been beating on a regular basis for the past 11 years (Williams leads their rivalry 17-2 and has not lost to the Russian since 2004). That ought to ease the pressure a little but it is not Sharapova that is the problem, it is that dratted “S” word.

If Williams can avoid all mention of that between now and Saturday evening, her dream might just come true.