“This was my first experience in an atmosphere like this—the whole stadium cheering for one person . . . It's incredible to see how much support she (Eugenie Bouchard) has. But I was just trying to stay in my little zone, zone it out.”—Shelby Rogers, on her three-set win over Bouchard, Montreal’s local megastar, in the second round of the Rogers Cup.

It was comparable to a rank journeyman beating Andy Murray in his first match at Wimbledon, or a qualifier taking down Roger Federer in his opener in Basel. It was as stunning a WTA upset as world No. 111 Virginie Razzano’s triumph over Serena Williams in the first round of the 2012 French Open, and it will take its place in the Upset Hall of Fame.

The only matches that get into that imaginary institution are the ones that absolutely nobody had seen coming. But that doesn’t always mean that the result is some sort of outlier; for in truth this was one that a sharp-eyed fan or pundit could have seen coming, albeit not from very far away.

Rogers, ranked No. 113 and who at 21 is just a year older than Bouchard, is shaped for today’s big-bang game. She’s 5’9” and she has plenty of muscle mass. She hits big groundstrokes, and that enabled her to rough up the Canadian who carried the expectations of the entire nation on her shoulders. Before the match, Bouchard had gamely declared that “pressure is a privilege.” She forgot to add—or hasn’t yet learned—that in the real world, into which she recently leaped with both feet, privilege also can be awfully burdensome.

“It was cool to see the support she has here and it’s fun to see that much support for tennis,” Rogers said afterward. “I knew what I was getting into so I was prepared for it. . .I know she’s a mega superstar up here.”

Rogers went into the match against the No. 5 seed (WTA No. 8) playing with house money; after all, what did she have to lose in that atmosphere? She was free to swing from the heels, and she was also coming into the match with an advantage few noted beforehand: She had beaten Bouchard in their only previous meeting, in an ITF event. Say what you will about the dazzling results Bouchard has put up at the three majors so far this year (two semis and Wimbledon final), but players remember such things.

Rogers, who won the demanding French Open wild-card playoffs hosted by the USTA in 2013, is on the upswing. Once again, we saw that there’s no substitute for confidence, and just plain feeling good about your game—feelings Bouchard might have had a little trouble mustering after her last match, a severe beating inflicted in the Wimbledon final by Petra Kvitova.

While Bouchard was resting and planning her Montreal homecoming, Rogers was tearing it up at the WTA Bad Gastein event. She had outstanding wins on clay over (among others) Carla Suarez Navarro and former French Open finalist Sara Errani before losing in the final to Andrea Petkovic.

In Washington last week, Rogers had a notable win over Alize Cornet, then lost to Marina Erakovic. She’s loped about 50 spots off her ranking in recent weeks. In Montreal, where Bouchard had a bye, Rogers turned in a good first-round win over another promising youngster, Ajla Tomljanovic. That was excellent seasoning prior to a match with a young lady who hadn’t played an official match in nearly a month.

Rogers, who now meets resurgent Caroline Wozniacki, is playing better than ever before, and any pro player in that position is dangerous to anyone, at any time.

“Yes, I would say that (I’m playing the best tennis of my life),” Rogers said, before meeting Bouchard. “I mean, every match isn't pretty. I’ve had some I guess ugly wins, I guess you could say. But I feel really confident on court. I’m moving well. I’m happy. I’m enjoying everything. I think it's definitely a high point in my career.”

And as we saw once again, one player’s high point can sometimes be a shocking low point for an opponent.