Second Serve: Your weekly tennis briefing

There is no escaping the fact that age is catching up with Novak Djokovic.

With his 38th birthday fast approaching, the evidence shows the 24-time Grand Slam champion's powers are waning.

But as the men's clay-court season begins in Monte Carlo, Djokovic looks in a much better place than a fortnight ago.

Finishing runner-up in Miami to Czech teenager Jakub Mensik showed that the world number five is not ready to roll into retirement yet.

"There is no doubt that [motivation] has become more difficult throughout my career but the performances in Miami give me more inspiration to keep going," Djokovic said.

The Serb veteran knows his serve needs to be potent if he is going to challenge at the upcoming French Open and Wimbledon.

Unable to rely as much on physicality against his younger opponents, Djokovic wants the accuracy of his opening shot - an underrated part of his game - to help limit the baseline rallies.

We saw the effectiveness in Miami.

Based on precision rather than power, he landed 79% of first serves - including a career-high 87% in the semi-final against Grigor Dimitrov - and only faced seven break points in his opening five matches.

"Now I know what it's like to be John Isner," he joked after beating Dimitrov.

Djokovic has not won a major since the 2023 US Open and claimed only one title last season - albeit the Olympic gold he had long craved.

That came on the Roland Garros clay, where he aims to win a standalone 25th Grand Slam title in June.

His other priority is becoming only the third man to claim a 100th tour-level singles title.

He will, however, have to come through a strong field in Monte Carlo, with 17 of the top 20 players competing.

Britain's Jack Draper is one of them, with Alexander Zverev and Carlos Alcaraz among the favourites.

What a time for Jessica Pegula to win the first clay-court title of her career.

On Sunday, the American claimed the Charleston Open title, beating 2020 Australian Open champion Sofia Kenin to reach a career-high ranking of third in the world.

Pegula, rated as one of the best players never to have won a major, has won 17 of her past 19 matches.

Another American success saw world number 507 Jenson Brooksby win the first ATP title of his career in Houston - having been given a qualifying wildcard.

Brooksby, 24, is the third lowest-ranked ATP champion as he continues his return.

Despite not playing last week, Draper reached a new career high, with Italian pair Flavio Cobolli and Luciano Darderi - who won the Bucharest and Marrakech titles - climbing the highest in the top 100.

The WTA Tour pauses for a week as the top players represent their nations in the Billie Jean King Cup.

This week's qualifying phase sees six groups of three nations compete in a round-robin format for a place in the season-ending eight-team finals.

Great Britain, who reached the semi-finals last year, are aiming to be one of the group winners who directly progress to November's finals in Shenzen.

Last year's runners-up Slovakia, the United States, Canada and Australia are also competing, while reigning champions Italy and hosts China have automatically qualified.

Most of the leading British players have been back at the National Tennis Centre over the past week to prepare for the clay-court swing.

Draper and Jacob Fearnley were seen perfecting their sliding techniques - a key skill on clay - while a behind-the-scenes LTA video showed Katie Boulter and Sonay Kartal practising on the surface before the BJK Cup tie in the Netherlands.

Heather Watson and Harriet Dart have already competed on clay after playing in Charleston, although both lost their first-round matches.

Cameron Norrie has also been in action, but the former world number eight lost to Italy's Mattia Bellucci in Monte Carlo qualifying.

In doubles, former world number one Jamie Murray reached the semi-finals of an ATP 250 event in Bucharest, while Emily Appleton made her third semi-final of the season at a WTA 125 event in Bogota.

With so many professional tennis tournaments taking place across the world, and across so many levels, it can be hard to keep up with everything from one week to the next.

As part of BBC Sport's commitment to offer more for tennis fans, Second Serve will be your weekly round-up of the biggest stories in the sport.

As well as the main talking point, you can see which ATP and WTA players are making significant progress - or struggling for form, how the British contingent are doing and what the next stops on the calendars are.

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