Ernests Gulbis will have to overcome a strong field if he is to retain his ATP Open 13 title and kick-start his faltering start to 2015.
The Latvian was victorious at the hard-court event in Marseille 12 months ago after defeating home favourite Jo Wilfried-Tsonga in straight sets.
It marked the second of two singles titles for Gulbis in 2014, who climbed to a career-high ranking of 10 last season.
However, the current campaign has yet to get going for Gulbis, who has failed to win a match.
Having lost to Jiri Vesely in Auckland in January, he suffered a shock first-round defeat to Thanasi Kokkinakis in five sets at the Australian Open.
Gulbis returns for the first time since playing in the opening major of the season in a bid to keep hold of his Open 13 crown, but doing so will be no easy task.
A potential quarter-final encounter with Frenchman Gilles Simon is on the cards, while the in-form Stan Wawrinka could await in the semi-finals.
Swiss Wawrinka won his opening tournament of the season in Chennai, before making a solid defence of the Australian Open title he won in 2014 by reaching the semi-finals.
Canada's Milos Raonic, on the opposite side of the draw to Wawrinka, is set for his first appearance in Marseille having started 2014 in good form - reaching the semi-finals in Brisbane before enjoying a run to the last eight at the Australian Open.
Also in action will be the French wildcard trio of Gael Monfils and Benoit Paire and Borna Coric.
However, Richard Gasquet and Julien Benneteau - who were originally scheduled to compete - have both withdrawn through injury.