The Round of 16 at the Shanghai Rolex Masters thins the field to its final eight, and Tuesday's slate brings a mix of rivalry rematches and fresh matchups across the hard courts in China. From a top-four seed defending his form against a clay specialist to a dominant head-to-head series renewed on familiar ground, there is plenty of intrigue to unpack.

Casper Ruud vs. Felix Auger Aliassime - Round of 16

This is a rivalry with genuine texture. Auger Aliassime leads the all-time head-to-head 5-3, and the most recent meeting went his way in a three-setter at Miami, where he recovered from dropping the first set to win 3-6, 6-1, 6-2. However, Ruud has won three of the four meetings before that, including a 6-1, 6-2 dismantling in the quarterfinal at Montreal and a 7-6(4), 6-4 victory in Turin's round-robin. The ranking gap is significant: Auger Aliassime sits at No. 4 in the world while Ruud is ranked 14th, and no odds are available to add further color. Auger Aliassime's superior ranking and the recent Miami win make him the logical favorite, but Ruud's head-to-head record over the middle stretch of this series shows he is far from a pushover.

Prediction: Felix Auger Aliassime in three sets.

Daniil Medvedev vs. Stefanos Tsitsipas - Round of 16

The numbers here are stark. Medvedev leads this head-to-head 10-5, and the recent results make the gap look even wider. He has won the last five meetings in a row, covering a Miami first round, a U.S. Open second round, a Basel quarterfinal, a Monte-Carlo third round, and most notably a Shanghai semifinal. That last result is particularly relevant: Medvedev already knows how to close out Tsitsipas on this very court. The ranking disparity is enormous, with Medvedev at No. 8 and Tsitsipas down at No. 84 heading into this match. No odds are listed, but the combination of a dominant head-to-head record, a five-match winning streak in the series, and a previous win at this exact tournament makes Medvedev a heavy favorite on any reasonable assessment.

Prediction: Daniil Medvedev in straight sets.

Botic Van De Zandschulp vs. Rafael Jodar - Round of 16

This matchup is a genuine unknown. Van De Zandschulp and Jodar have never met, so there is no head-to-head history to draw from, and no odds are available either. The ranking difference is notable: Jodar comes in as the higher-ranked player at No. 23 versus Van De Zandschulp's No. 55, which makes the Spaniard the nominal favorite. With no prior meetings and no odds to reference, the ranking gap is the clearest guide available.

Prediction: Rafael Jodar in two sets.

Tommy Paul vs. Zizou Bergs - Round of 16

Paul and Bergs have met once before, and it was not close. Paul won 6-1, 6-2 in the second round at Indian Wells, a result that leaves Bergs with plenty to prove in a rematch. Paul is ranked 28th to Bergs's 40th, so the ranking edge also lines up with the head-to-head advantage. No odds are provided, but both metrics point the same direction. Bergs will need to show a significantly different level of performance than he managed in Indian Wells if he is to advance.

Prediction: Tommy Paul in straight sets.