NEW YORK -- Serena Williams insists she didn't have any flashback nightmares when she first stepped on the grounds of the US Open this year.

"I always feel really happy walking out at any Grand Slam," she said. "I feel so many wonderful memories and moments. I feel really good about it. Same with coming here to New York. It's always a good feeling."

A year ago, it wasn't all good feelings for Serena after she was stunned in the semifinals by Italian Roberta Vinci, bringing a shocking halt to Serena's bid to become the first person since Steffi Graf in 1988 to win the calendar year Grand Slam.

Vinci -- who went on to lose in the final to fellow Italian Flavia Pennetta -- entered last year's tournament facing odds of 300-1 to win it. Serena had been 43-1 against unseeded opponents at the Open in her career.

One year after that Buster Douglas-like upset, Vinci on Monday won her first-round match in Arthur Ashe Stadium over Anna-Lena Friedsam, 6-2, 6-4.

"It's tough to repeat of course the results of last year," Vinci said. "But I'm No. 7, so of course I have a lot of pressure. They expect me semifinal, quarterfinal, step by step and match by match."

Serena, the top seed and world No. 1, is set to take the Ashe Stadium court under the lights on Tuesday night against Russian Ekaterina Makarova, against whom Williams is 4-1, including a victory in the 2014 semifinals.

"That’s going to be a test for Serena," Chrissie Evert said. "She’s just a dangerous first-round player so that’s interesting."

Once again, Williams will be chasing history in Flushing Meadows.

No, she's not on pace for a Grand Slam, but she can win her 23rd major title in the Open Era, which would surpass Graf's 22. Margaret Court holds the all-time women's record with 24 major titles.

"More importantly, she’s playing for breaking my record of six US Opens," joked Evert, referring to Serena shooting for a seventh US Open title. "Not the same pressure she faced last year, but there will be a little bit of pressure."

"I think I am just more relaxed [than last year] for sure," Williams said.

Williams comes into the Open bothered by a shoulder ailment and having not played much tennis this summer. She said her shoulder first began to bother her the day after she won the Wimbledon final against Angelique Kerber, the German who is seeded No. 2 here and won her first-round match over Polona Hercog of Slovenia via retirement, 6-0, 1-0.

After Wimbledon, Williams was stunned in the Round of 16 at the Olympics by Elina Svitolina of the Ukraine, and then skipped the event in Cincinnati because of her shoulder.

"I have not played a lot, I haven't practiced a lot, but I'm just now starting to feel a little better," Williams said. "Hopefully just every day I will keep going higher."

Looking ahead, Williams could face No. 5 Simona Halep in the quarterfinals; No. 6 Venus Williams (whom Serena beat in the quarterfinals in 2015) or No. 4 Agnieszka Radwanska in the semis; and No. 2 Kerber, No. 8 Madison Keys (the top American woman not named Williams) or even Vinci in the final.

As is always the case with Serena in New York, more history will be on the line.

"The US Open is obviously a special place," she said. "I think usually I prefer to play more coming into the final Grand Slam of the year, but there is nothing we can do about it. You just have to make the best of every single opportunity. That's all I can do now."

Follow Adam Zagoria on Twitter @AdamZagoria for updates throughout the U.S. Open.