Not long after, the weakness had spread to the veteran winger’s back.
Eaves managed to battle through and suit up for two regular-season games, he even scored in one, but whatever was wrong eventually started to affect his breathing.
"It all evolved very quickly," he recalled in a phone interview Tuesday. "Before I knew it, I was in the intensive care unit. It was pretty scary.
"I went from the best shape of my life to an ICU in about a month."
Eaves was initially diagnosed in October with what was suspected to be Guillain-Barre syndrome, a rare disorder where the immune system attacks the peripheral nervous system, sometimes resulting in death.
"My body started to neurologically shut down," said the 34-year-old, who has 132 goals and 110 assists in 626 games with six NHL teams. "My three kids and wife had an upper respiratory virus. We had just moved out to California. I was taking care of the four of them, and then a couple days before camp I started to get it in my chest.
"Probably about a week later I started to feel the power in my legs go out."
Eaves spent time in hospital recovering as doctors tried to figure out what was wrong, eventually learning some two months later that he in fact didn’t have Guillain-Barre, but had instead been struck down by a "post-viral syndrome."
Relieved he didn’t have Guillain-Barre, a shoulder injury suffered during an initial rehabilitation attempt caused further problems before Eaves travelled to Florida for further treatment.
"I was very fortunate to have a trainer that deals with neurological disorders," said Eaves, who will be in Toronto on Wednesday for the Smashfest charity ping-pong tournament along with a number of fellow NHL players. "Probably the hardest workouts I’ve ever had to do because it was neuro more than muscular. We just went through the whole body.
"I don’t know what he did, but I started getting everything back working and firing."
Eaves, however, wasn’t initially thinking about anything other than a return to normalcy.
"I went down to Florida to be a father again," said Eaves, whose mountain-man beard is rivalled in NHL circles by only Joe Thornton and Brent Burns of the San Jose Sharks. "Playing wasn’t really on my radar. I was just trying to go get my life back.
"It was really hard on the family. I’m surrounded by great people. Everybody grabbed the rope."
The Ducks acquired Eaves from the Dallas Stars as a rental prior to the trade deadline in February 2017, but liked what they saw and inked the pending unrestricted free agent to a three-year, US$9.45 million contract extension.
He was coming off a combined 32-goal season in 79 games, and had found good chemistry with Anaheim, where he scored 11 times in 20 outings before the health scare derailed him last fall.
"The whole season was hard to watch," said Eaves, the owner of 11 goals and 12 assists in 83 career playoff games. "It was tough."
The son of former NHLer Mike Eaves did return to the ice in late February, but determined his ailing shoulder couldn’t endure the rigours of a Ducks’ playoff push. He opted for surgery in early March — Anaheim was swept by San Jose in the first round — and hopes to be ready when camp opens in just over six weeks.
"It was a long year trying to figure things out," said Eaves, the 29th overall pick in the 2003 draft by the Ottawa Senators. "I feel great right now."
He’s also made a habit of feeling great after Smashfest, where Eaves is the three-time defending champion.
In its seventh year, the event where hockey players fire ping-pong balls across tables at one another to raise money for concussion and cancer research is hosted by Dominic Moore with the help of the NHL Players’ Association.
Eaves played ping-pong growing up, but really got hooked after getting to Ottawa as a rookie.
"(Senators captain) Daniel Alfredsson was a stud," Eaves said. "He used to just spank me. We’d almost be late for warmup because we’d be having so much fun playing."
This year’s event is scheduled to include Toronto Maple Leafs forwards William Nylander, Zach Hyman and Connor Brown, as well as Carolina Hurricanes counterpart Jeff Skinner.
"I’m really excited," Eaves said. "It’s a fun night."
And a night that, not long ago, was probably the furthest thing from his mind.