Serena, Federer and teens lead U.S. Open midterm grades

NEW YORK -- We have four rounds to go in the year's fourth Slam. As I write this, the draw has been depopulated of five of the top ten women's seeds -- while all top ten men remain. We've had a 15-year-old girl and a 34-year-old man make smashing debuts. A visit from 23 (Michael Jordan) inspired Roger Federer, age 33. Numerology is not on the syllabus but herewith, our midterm grades. 

A:

Five-time U.S. Open champs with 17 career majors, born midway through 1981: Which is to say, both Roger Federer and Serena Williams are looking strong.

Watch: Roger Federer hits a ridiculous sliding lob for a winner

​Mirjana Lucic-Baroni: A Wimbledon semifinalist in 1999 returns to the second week of a Slam, authoring a lovely comeback story.

Thirty-somethings: A full quarter of the men’s field was north of 30 when the event started. One of the oldest, Victor Estrella Burgos, 34, did himself proud playing in his first major.

The teens: CiCi Bellis, age 15, left with no prize but a mother lode of well-earned confidence. Now leave her alone! Belinda Bencic is also a future star, beating No. 6 Angelique Kerber for a spot in the second week.

Young American CiCi Bellis' Cinderella story incomplete at U.S. Open

​Gael Monfils: For being tennis’ great crowd-pleaser, but for this shot specifically.

Dominic Thiem: Der real deal.

Victoria Azarenka: A finalist two years running, with emphasis on running: her movement is improved and she’s back in week two.

CBS: In its last year broadcasting the event, the network hasn’t scrimped. And inviting Dick Enberg to take a well-deserved victory lap is a nice touch.

B:

Brash young Aussies: Fair dinkum Nick Kyrgios turns in another strong performance. Bernard Tomic adds to considerable history of drama by withdrawing before his second rounder against David Ferrer.

Mailbag: Did Venus Williams' doubles match affect her singles play?

​Venus Williams: She plays singles and doubles. Age and autoimmune disease be damned, she’s playing three-set matches with few ill effects. But her inability to serve out Sara Errani in the third set will haunt her for a long time. What happened to the mentally impregnable Venus?

Night matches: You really feel the absence of Rafael Nadal, Li Na and bankable Americans. But thanks to some resistance and flash from the cannon fodder -- hat tip: ThomazBellucci, SoranaCirstea, Sam Groth -- the matches entertained.

Counterpunchers: The conventional wisdom is that an arsenal of weapons is a pre-requisite to winning majors. But from David Ferrer to Kei Nishikori to Errani and a resurgent Caroline Wozniacki, it was a good week for the backboards.

C:

American men: Three Yanks made it to the second round, the most dismal showing ever. A bit of perspective here: 20 years ago, that number was 16. Thirty years ago, it was 33. The gap between the commerce of the U.S. and the failure to alchemize that into top players is, sadly, striking.

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​USTA seat allotments: The secret is out: the grounds pass is the way to go and you’re often better off avoiding setting foot in Ashe entirely. Upshot: the televised matches play to oceans of empty seats, while match-ups on the outer courts were oversubscribed.

Sloane Stephens and Madison Keys: Two best Americans not named Williams make a combined 123 errors in their comparably disappointing early defeats.

Ana Ivanovic: You beat Maria Sharapova in three brutal sets. Less than two weeks later -- at a major on the same surface, you’re barely competitive against Karolina Pliskova?