A foot injury - and then surgery - had put her career on ice for 10 months and her ranking had nosedived to 323 in the world.
Ahead of the French Open 2018 clash, the 23-time Grand Slam victor called out the parts related to her in Sharapova's autobiography as "hearsay".
The 2012 and 2014 Paris champion, who missed the 2016 tournament because of a doping ban and a year ago when she was refused a wild card, was broken six times, committed 27 unforced errors and won just five points on her own serve in the second set.
Halep's fourth chance to win her first Grand Slam title will come against reigning U.S. Open champion Stephens on Saturday.
Stephens has won both head-to-head encounters, including the Grand Slam final debut for each at NY in September. Halep has won her last four matches against Stephens - two last summer at the Citi Open and Western & Southern Open. I will play my game against her, as I did past year. Her wins over Muguruza and Angelique Kerber have taken more than 3.5 hours combined. At the Miami Open in March, she won the title, beating four major champions in a row.
However, her sights now turn to the final where she is desperate to erase the memories of last year's horror show where she surrendered a set and a 3-0 lead to lose to Jelena Ostapenko.
But she has not dropped a set in this year's tournament and dominated Sharapova with booming groundstrokes and superb returning that earned six breaks.
Muguruza had thrashed Maria Sharapova in the quarter-finals but Halep was a different proposition entirely, and it seemed she knew it.
Kerber again failed to serve out the set after breaking back for 6-5 as Halep forced a breaker. "I think Serena hated me for being the skinny kid who beat her, against all odds, at Wimbledon", Sharapova wrote. This year, she was two points from defeat in the third round against Camila Giorgi of Italy before turning that match around.
"But to have had the victories that I have had, to have the results that I have, obviously moving a step in the right direction".
"So tomorrow is going to be a big challenge for me". It's just how it's happened for me", Stephens said, "I think once I get going in a tournament, I'm pretty consistent, which is good.
"I have just to stay strong, to try to make her uncomfortable on court", Halep said, "and to try to play my game".
Muguruza improved in the early stages of the second set, holding serve for the first time and backing it up with a break on her way to a 3-1 lead.