Wayne Rooney out of Saint-Etienne vs. Manchester United After Return to Training

Manchester United striker Wayne Rooney has not been named in the 20-man travelling squad for the club's trip to face Saint-Etienne in the second leg of the UEFA Europa League last 32 on Wednesday.

United confirmed Rooney would not be in the squad in a report from Gemma Thompson on their official website. The England international is a notable omission, despite having trained with the original 23 players eligible for selection, per another report from Thompson and Ryan Grant on United's website.

Both Thompson and Grant noted how Rooney has "missed the last two matches as a precaution." The club's all-time leading goalscorer may have been back in training, but he was part of a group removed from the main core, per BBC Sport's Simon Stone:

Rooney's latest omission will only raise doubts about his future beyond this season. There has even been speculation 31-year-old Rooney could be sold to the lucrative Chinese Super League ahead of the country's transfer deadline later this month, according to James Ducker of the Daily Telegraph.

Rooney has made only 17 starts across all competitions since Jose Mourinho succeeded Louis van Gaal as manager last summer, per WhoScored.com. The number is low considering Mourinho's United boast the unique distinction of being the only Premier League side still active in four tournaments.

Yet United's busy schedule could explain why Rooney will not travel to France. United are already on the cusp of progressing, leading 3-0 from the first leg. So it makes sense for Mourinho to not want to risk a player he may need for Sunday's EFL Cup final against Southampton instead.

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Indeed, Stuart Mathieson and Rob Dawson of the Manchester Evening News have insisted Rooney's absence from European duty is simply due to the fact the "second leg will come too soon."

With a cup final to negotiate, as well as progress in Europe, Mourinho must balance the demands on his squad, especially since United still chase precious Premier League points in the race for a top-four finish.