It was Kids’ Day in Rotterdam, but it quickly became clear that the clash between Juan del Potro and Gael Monfils was all about stress management. Would del Potro’s creaky left wrist withstand the pounding in his return to match play, and would Monfils hold his sometimes wayward mind together playing his sixth match in the last eight days?

Despite suffering some turbulence while serving to close out both sets, del Potro delivered a 7-6 (6), 6-3 victory in his first match since suffering a surprising five-set loss to Roberto Bautista Agut in last month’s Australian Open.

You’d think the mercurial Monfils would carry the confidence from sweeping Richard Gasquet in the Montpellier final on Sunday to capture his fifth title and return to the Top 25, but the elastic Frenchman looked jittery from the start, making del Potro wait at net while he wrapped his overgrip before the coin toss, then delaying the start of play because he was unsettled by some chatter and a few giggles from kids in the crowd.

Compounding a distracted start, Monfils dropped serve in the opening game, only to benefit from a double-net cord winner that dribbled over to give him the break back at 1-all. Holding for a 2-1 lead did little to calm Monfils, who was still chirping at chair umpire Carlos Bernardes about crowd noise during the changeover. “The start of the match was a mess,” Monfils said.

Cleaning up his play, the top-seeded Argentine broke first for 4-3 when Monfils sailed a wild backhand, then bounced his black Wilson racquet on the court. Serving for the set with triple set point at 5-4, del Potro’s rust became as visible as his red wristbands. Monfils responded with three crunching forehands, del Potro double faulted, and finally missed a forehand down the line to drop serve.

Monfils, who was 4-0 in tiebreakers this season, earned the early mini-break for a 4-2 lead in the breaker, but tightened up and clanked a double-fault serving at 5-3. He saved a fourth set point with an ace, but del Potro finally closed the 65-minute opening set with a crackling serve down the middle.

Playing without any taping on his wrist, del Potro, who visited the Mayo Clinic in Minnesota for treatment last week, began to loosen up, commanding the center of the court and firing his massive forehand to make Monfils run corner to corner. Del Potro, who won their last meeting in Rotterdam last year, began imposing his advantage in the forehand exchanges to break at 30 for a 3-1 second-set lead.

When del Potro, who can swing with the vicious intent of a man trying to dent the back wall with the tennis ball, is landing his forehand with depth, Monfils is prone to eventually spinning his forehand short or steering it wide in response. Monfils’ footwork isn’t as precise as, say, Nadal, Djokovic, or Murray, but the Frenchman’s raw speed is riveting. It also provides a measure for just how powerful del Potro is when he can blast forehands that leave Monfils lunging at air.

Monfils fought off a pair of match points before del Potro created closure after 99 minutes. It was del Potro's 24th straight victory as a No. 1 seed: He's won his last five tournaments when heading the top of the draw, and should be satisfied by his start today as he aims to reach his third straight Rotterdam final.