There was no particular cause for alarm when top Canadian Milos withdrew from this week's ATP Tour event in Delray Beach.
But now, the 25-year-old has also withdrawn from next week's event in Acapulco – a larger tournament with three times the prize money and a better field.
The ATP wouldn't confirm the withdrawal, but did come back Saturday and confirm that Raonic had pulled out because of an "ongoing hip injury."
With the first-round Davis Cup tie against France looming in two weeks, there has to be some cause for concern.
Raonic hasn't played since losing the Australian Open semi-final to Andy Murray at the end of January, a match he appeared to have well in hand until an adductor issue that he said had also bothered him in his 2016 season debut in Brisbane (he won the tournament despite it) flared up again.
The deadline for Davis Cup team nominations is 10 days before the tie begins – in other words, next Tuesday - although some squads have already announced their lineups.
The French have nominated Richard Gasquet, Gilles Simon, Gaël Monfils, Jo-Wilfried Tsonga and, as a fifth player should he be needed, doubles specialist Edouard Roger-Vasselin.
All four players are ranked among the top 16 on the ATP Tour, so obviously Raonic's presence is key to Canada's hopes.
Several members of the French team are headed down to Guadeloupe, the site of the tie, to adapt to the climate and the red clay, which is the surface that will be used. Roger-Vasselin, scheduled to play doubles with Canadian Vasek Pospisil at a tournament in Dubai next week, pulled out of that commitment.
On a related note, Raonic's NBA All-Star celebrity game teammate Genie Bouchard, who took a wild card into next week's big WTA Tournament in Doha, Qatar, drew a qualifier in the first round.
That qualifier turns out to be Anastasija Sevastova of Latvia, once a young, promising player who made the fourth round of the Australian Open at age 20 and reached a career high of No. 36. Then, just as swiftly, she announced her retirement right after her 23rd birthday. She returned in 2015 and after beginning the season with no ranking, finished just outside the top 100. She's currently at No. 95.
If Bouchard wins that, she could face Elina Svitolina of Ukraine in a rematch of the 2012 Wimbledon final. The big seed looming in her section of the 48-player draw is No. 1 seed and Australian champion, Angelique Kerber of Germany.