Serena's chances, Big Three spoilers and other Week 2 US Open questions

Serena's win a highlight of Day 7 (1:42)

Catch the top highlights from Day 7 of the US Open, including a nice point by Serena Williams in her victory. (1:42)

NEW YORK -- With the first week of the 2019 US Open in the books, we asked our tennis experts to reflect on the top moments so far at the Billie Jean King National Tennis Center -- and what will be on their radars in Week 2.

From continued Coco-mania to Taylor Townsend's resurgence to Big Three spoilers, Week 1 at US Open had its fair share of drama.

Here's what our experts had to say:

With Novak Djokovic's early exit, who will take advantage of their opportunity/opening the most?

Jerry Bembry: Roger Federer. He hasn't won a major since the 2018 Australian Open. A path to the final has just been cleared.

Peter Bodo: The evidence that Daniil Medvedev is the second-best player (after Dominic Thiem) who hasn't won a major is mounting. But he's leg-weary after his stellar month of August, so give the nod to former US Open champion Marin Cilic. He struggled early this year and has fallen out of the top 20, but the powerful, rangy 30-year-old has been to two Grand Slam finals, seems to have found his game again and carries a serve that can take the racket out of anyone's hand -- all factors that could help him take out Rafael Nadal.

Simon Cambers: It has to be Federer. With Djokovic out of the way, and given the improvement from Federer over the last two rounds, the 38-year-old will fancy his chances of making the final. Could we have a Nadal-Federer final at the US Open?

D'Arcy Maine: Stanislas Wawrinka is the obvious answer here, and he looked good in the win over Djokovic. Sure, the defending champion wasn't feeling his best and struggling with his shoulder, but that shouldn't completely take away from Wawrinka's night. He had nine aces, won 84% of his first serves and was just the better player. The 2016 US Open champion will have his hands full with Medvedev in the quarters, but he has proven he knows what it takes to win in Queens before, and certainly looks capable of reaching the semis, at least.

We are midway through the US Open. What are your predicted finals matchups?

Bembry: Federer versus Nadal on the men's side, and Serena Williams versus Naomi Osaka -- a repeat of last year's dramatic final -- on the women's side.

Bodo: On the men's side, Nadal and Federer will meet in a US Open match for the first time next Sunday. It's almost fated, after the kind of Grand Slam year we witnessed. It started with Stefanos Tsitsipas's Next Gen breakthrough to the Australian Open semis, then came a familiar helping of Nadal's clay-court expertise at the French Open and was sweetened with a big dose of Djokovic at Wimbledon. What better way to end this Grand Slam season?

On the women's side, pencil in Serena in the bottom half. The top half, while chock full of surprising guests, still features No. 1 seed Osaka. Gritty Canadian Bianca Andreescu might be the biggest obstacle standing in the way of Osaka meeting Williams. Osaka's big win against Coco Gauff will be jet fuel for her confidence. Let's face it, people would love to see a Serena-Naomi rematch. It looks as if it will happen.

Cambers: Federer versus Nadal, and Osaka versus Elina Svitolina.

Maine: Federer and Nadal have never met in New York, and I think this might just be the year. In the championship match, no less. With Djokovic's early exit, Federer, who would have faced him in the semis, can take advantage of his absence and set up a long overdue US Open title match with his longtime foe.

For the women, I can't resist. I'm calling a rematch of the 2018 final between Williams and Osaka. They're both playing so well right now, it seems as if they are on a collision course with destiny. A potential semifinal match against Bianca Andreescu will be tricky for Osaka and could easily be a three-set thriller between two of the best young players in the game.

Which player has surprised you the most in the men's and women's draws?

Bembry: Townsend's run has been the biggest shocker of the tournament, and the confidence she has gained here can make her a problem in the future. Gael Monfils on the men's side, simply because of his shocking 360-degree slam to win a second-round match. LeBron James would have been proud.

Bodo: Grigor Dimitrov put together a terrific first-week run, culminating with a win against a very tough rising Next Gen Aussie star, Alex De Minaur (he eliminated No. 7 seed Kei Nishikori). Dimitrov, ranked No. 3 as recently as January 2018 following his career year, slumped terribly over the ensuing months. Just 1-7 between his fourth-round loss at the French Open and the start of this tournament, Dimitrov came into the US Open ranked No. 78.

Townsend has made a surprising run, but take that with a caveat: her abundant talent and creativity have been manifesting for years. Still, this tournament was supposed to be all about Gauff, Serena's quest for No. 24 and Osaka's attempt to defend her title. Then the forgotten prodigy Townsend pops up and beats Wimbledon champ and No. 4 seed Simona Halep in the second round and backs it up with a third-round win.

Cambers: Townsend. Not through her play -- I have always thought she was a fantastic player to watch, with all the ability in the world -- but I've been pleasantly surprised by her consistency and ability to maintain her level throughout.

Maine: Medvedev certainly gets my vote for most surprising moment and heel turn, but on a strictly tennis front, Dimitrov's quarterfinal run was somewhat of a shock. He has dropped to No. 78 and hasn't reached the quarters at a major since the 2018 Australian Open and never made it this far in Queens. Sure, he hasn't had the toughest opponents along the way and next faces some guy named Federer, but it has been nice to see him in the second week of a Slam again.

On the women's side, it would be virtually impossible not to pick Townsend and Kristie Ahn, two Americans who have shocked the field thus far -- Townsend with her huge win against Halep to reach the fourth round of a Slam for the first time, and Ahn with her first Grand Slam win and advancing to the round of 16. It's great to see hard work and perseverance pay off.

What does Serena need to do in Week 2 to lock up her record-tying 24th Grand Slam title?

Bembry: Keep doing what she's doing -- playing smart, focused tennis. With two of the top three seeds (Ashleigh Barty and Halep) out of the tournament, there is a somewhat clearer path to history.

Bodo: The challenge for Serena will be keeping her cool, because the pressure will mount with each passing game, set and match. Williams shares the tournament lead with Elise Mertens for service games won (36 of 39, 92%), and while she's only No. 4 in the ace count, she leads the field in an even more significant serving category -- 48% (68 of 143) of her serves have gone unreturned. That's a huge, critical number. It's hard to see anyone beating Williams if she maintains that pace. But the big question is how Williams will react to the pressure after having come so close to securing No. 24 only to fall short.

Cambers: Stay healthy, first of all. That ankle roll Sunday was close. And then, try, somehow, to keep the stress levels down. She's moving so much better than even a few months ago and playing great. It's really going to be a battle in the mind as well as on court.

Maine: When it comes to skill and talent, Serena is still among the best of the best. And despite a scare with her ankle in her fourth-round match, she appears to be feeling the healthiest she has felt in some time. For her to win, it probably will come down to mental fortitude. Can she keep her nerves in check during a championship match, or even a run to the final, with so much on the line? She obviously has struggled in her three major title matches since coming back from the birth of her daughter, and it seems as if each loss is a little tougher to overcome. If she's able to focus solely on the match in front of her and not the weight of history and expectations, she certainly could take home No. 24.

Given the run by Coco Gauff and other female teens at the Open, should the WTA reevaluate its age-restriction rule?

Bembry: Let the kids play if they're talented enough, as often as they want. If these youngsters can perform at the highest level -- and Gauff's level has been pretty lofty -- there's no reason to deny them the opportunity. You can burn out on tour whether you are 15 or 17. A key to a young player's success is often family guidance, and it's clear Gauff's parents have their daughter on solid ground.

Bodo: Gauff is an outlier. It would be a mistake to change the age-eligibility restrictions simply because of her talent. The Grand Slams do not have to abide by the WTA rules regarding age restrictions, so a combination of the access to the majors and the number of WTA events allowed seems pretty good at all age levels. But let's take this out of the theoretical realm. Does anybody think Gauff would be best served by going to play the Asian swing of the tour in the fall? We don't have sufficient data on how she would handle a heavier diet of pro tennis. Gifted as she is, Coco is still only 15. Had she gone deeper into the tournament, I might feel differently. But her loss to Osaka shows she still has a lot to learn and process before she's mentally and physically ready to play loads.

Cambers: No. I know they're always reevaluating it, year on year, but I think 10 tournaments as a 15-year-old is enough. At that age, players are still developing, physically and mentally, and the rule is there to protect them. Hopefully, Gauff and other teens coming through will have longer careers as a result of the rule.

Maine: How much time do you have? There's a valid case to be made here for either side of this debate. Gauff has certainly showed she's more than capable of dealing with the pressures and competition of the tour despite her age, and it feels unfair she's not able to play in as many tournaments as she wants to gain that valuable match experience. But, the rule is in place for the right reasons (See: Capriati, Jennifer) and no one wants to see the burnout of a promising young player when it can be avoided. There might not be a right answer here; perhaps it needs to be evaluated on a case-by-case basis.