Arjen Robben Will Be Bayern Munich's Player to Watch in Pre-Season

Bayern Munich's pre-season began on Monday with the club severely short of personnel, about half the squad showing up for Carlo Ancelotti's first day of training. It's the price a big club must sometimes pay in order to have great players—they often are successful in international tournaments and miss the early days of the following campaign.

For Bayern, 11 players—including new signings Mats Hummels and Renato Sanches—featured at Euro 2016 and will join the squad late, along with Copa America Centenario winner Arturo Vidal.

There were several longstanding Bayern men in Ancelotti's training from the get-go, players whose countries hadn't qualified for international tournaments, those who were injured or who had retired from international football.

One such player is Arjen Robben, who will have a point to prove and is Bayern's man to watch during the pre-season. He's determined to put his best foot forward, and began individual training a week early.

Last season was quite tumultuous for Robben, who struggled with injuries and had to watch his national team slide out of contention for a spot at Euro 2016.

The winger started his last Euro qualifier in 2014, and various muscular problems saw him make just one 31-minute outing in a loss against Iceland out of the Netherlands' final six games in qualifiers. The Dutch lost three of their last four and finished fourth in Group A, five points behind third-placed Turkey.

As captain of his national team, it was a big blow for the 32-year-old, who was rumored to have been contemplating international retirement. He scuppered that talk in a January press conference, per ESPN's Stephan Uersfeld, but the fact remains he will be 34 by the time of the 2018 World Cup. For a player of his age, a lot can go wrong in two years.

Robben would go on to miss 31 of Bayern's games in 2015-16, per Transfermarkt, appearing in just 22 matches in all competitions. It was his worst season since joining the Bavarians in 2009 in terms of goal productivity, as he scored seven times and gave three assists.

Perhaps most critically, though, it was his least influential campaign in Munich. The German giants won the Bundesliga by a mile and triumphed in the DFB-Pokal, while also reaching the Champions League semifinals. They played great football, and wingers Douglas Costa, Kingsley Coman and Franck Ribery ensured that there was no shortage of class on the flanks.

Previously, Bayern had risen and fallen with Robben's form. In the spring of 2010, he carried his otherwise underwhelming team to the Champions League final. Two years later, the Bavarians finished runners-up in three competitions with the Dutchman missing key penalties in the Bundesliga against Borussia Dortmund and in the Champions League final against Chelsea.

In 2013, Robben was the man who assisted the opener and scored the winner against BVB in the Champions League final. History would have predicted a struggling Bayern in 2015-16, but in reality, Robben was hardly missed.

Accordingly, Robben now is at a crossroads in his career. He's no longer the main man in the Bayern attack—he and Ribery were replaced as the headline duo last season by Thomas Muller and Robert Lewandowski. The Frenchman accepted his support role and did quite well after recovering from injury, and he will be a good model for the former Chelsea and Real Madrid man to follow.

To his benefit, Robben will have plenty of chances in preseason to showcase his talent and to build form.

Whereas Coman will return late due to his participation in France's run to the Euro 2016 final, and Costa was forced to withdraw from Brazil's Olympic team due to an injury, Robben will have a full pre-season to train. And afterward, he won't have to worry about competing for a starting role, at least for the first couple weeks of the campaign as the alternatives enjoy their post-tournament rest and later build fitness after the hiatus. 

It won't be entirely easy for Robben, who hasn't played since the beginning of March due to injury. He'll be short of match practice and may need time to adjust. But having played limited minutes over the last year—especially in recent months—also means he will at least be a bit fresher, which could be important, particularly for a player of his age.

Bayern missed out on a treble last season and could have used Robben's influence in the Pokal final and the Champions League knockout rounds, when they struggled at times. And perhaps in 2016-17, they'll need him at his best.

Much is riding on how Robben reacts to the new situation as a supporting player at Bayern rather than the headline act, and how his body fares under the strain of a difficult season. This all begins in pre-season, and how he fares in the coming weeks may provide substantial insight into how he'll do for the remainder of the campaign.

As many Bayern stars take extended vacations, Robben is the one to watch among Ancelotti's squad this pre-season.

@Mr_Bundesliga