Manic Monday kicks off on No. 1 Court with this intriguing fourth-rounder between two players with title dreams. Halep reached the semis at Wimbledon two years ago, and she has played the steadiest tennis of her season so far during the first week. She hasn’t lost a set, or even been pushed, in three matches. While Keys, a quarterfinalist here in 2015, has dropped the middle set in two of her matches, she has rebounded quickly both times. That makes it nine straight victories on grass for Keys, who won the tune-up event in Birmingham. Under coach Thomas Hogstedt’s watch, one bad game for Keys no longer tends to lead to three bad games, or more. Halep and Keys split their two previous meetings, both of which took place in 2014, and neither of which was on grass. If both are confident and playing well, as they are right now, who should prevail? It’s a tough call: Keys can overpower the smaller Halep, but Halep is smoother and less prone to wild swings in form. On grass, I’ll go with power.

Winner: Keys

This is one of those matchups that fans circled the day the draw came out, and for good reason. While Serena can have a bad day, and possibly lose, against dozens of opponents, there are few who have the game and the experience—the 31-year-old Kuznetsova has won two majors—to stay with the world No. 1 even when she’s sharp. The American is 9-3 against the Russian, and she rolled past her in their last meeting, on clay in Rome in May. But Kuznetsova beat Serena the month before on hard courts in Miami, and against Sloane Stephens in the last round she looked determined to get another shot at her. Stephens led 5-2 in the third before Kuznetsova came back to win 8-6. Still, this is the farthest Kuznetsova has gone at Wimbledon since 2008, which makes me think that grass doesn’t do much to help her varied, topspin-heavy game. Serena, a six-time champion here, seems to like the green stuff just fine.

Winner: S. Williams

This match, last up on Centre, will give Murray-Kyrgios the career Slam: In 2015, they met at the Australian, French and U.S. Opens; why shouldn't they bring their buddy act to Wimbledon as well? Murray certainly shouldn’t mind; he’s 4-0 against Kyrgios, with the loss of just one set. Does Kyrgios have any chance of changing that in Murray’s home away from home, Centre Court? The Aussie’s athletic, serve-based game obviously works well on grass; his career record at Wimbledon is now 10-2. He’s no stranger to Centre Court, either; that’s where he announced his talent to the world by upsetting Rafael Nadal two years ago. So far, though, Kyrgios’ style hasn’t stacked up well against the Scot’s. Murray is one of the game’s best returners, as well as one of its steadiest and most thoughtful baseliners. With his speed and strength, he’s able to absorb Kyrgios’ pace and counter it with his own. And while Murray seems to enjoy being the calmer presence on court when he faces the tour’s resident loose cannon, Kyrgios may have too much respect for Murray to go after his friend in the hammer-and-tongs style that tends to lead to his best tennis. Murray has lost before the semis just once at Wimbledon since 2008, when he was blitzed by Grigor Dimitrov two years ago. Kyrgios could also do that to Murray, and he’ll beat him eventually. But with Novak Djokovic out of the tournament, there’s too much on the line for Murray to let it happen on Monday.

Winner: Murray