Kings teammate Justin Williams had suffered what Coach Terry Murray called a "lower-body issue" during the morning skate, leaving a void on the team's top line for that night's game against the Dallas Stars.
But Simmonds hadn't heard. That's why the 21-year-old's eyes lit up when he walked into the team's dressing room before the game. Murray had written on the drawing board that Simmonds, or Simmer as his teammates call him, would take Williams' place alongside left wing Ryan Smyth and center Anze Kopitar.
"That was huge for me," said Simmonds, who had two goals and an assist in the five games that Williams was out. "That's when I really started to step it up."
Did he ever. A game doesn't go by now it seems without Simmonds making a critical play -- be it a goal, an impossibly perfect backhand pass or a game-changing defensive move -- as the Kings (18-10-3) work to make the playoffs for the first time since 2002.
Entering tonight's game against the Western Conference-leading San Jose Sharks (19-7-5), Simmonds has a team-leading plus-12 rating, is tied for second with Smyth and center Jarret Stoll in goals (nine), is eighth in points (19) and has eight points in his last seven games -- including his first career penalty shot.
Drafted by the Kings in 2007 (second round, 61st overall), Simmonds said his temporary promotion to the top line exemplified the "trust Terry shows in me." And that, he said, is all he needed.
Murray, however, points to Simmonds' off-ice routine that included shooting pucks after practice and workouts last summer that helped strengthen Simmonds' shoulders.
Simmonds "deserves the credit," Murray said.
"If you're going to be a good hockey club and make the playoffs," he added, "you need to have secondary scoring."
The Kings have proved that as they battle scoring slumps -- including ones from Dustin Brown (14-game goal drought), Kopitar (13-game goal drought) and Williams (three goals in 12 games) -- and injuries.
"Sometimes you're going to get cold and sometimes you're going to get in a slump," said Kopitar, whose 35 points puts him among the league leaders. "It's good to know that somebody can step up and make plays and score goals like Simmer does."
Yet, after hearing of his promotion to the top line, Simmonds said his first thought was, "Just don't mess up."
Frequent conversations with Kopitar and Smyth during the first couple of shifts helped Simmonds relax.
The offensive part of his game soon was distinguished by the same relentlessness he showed on defense, which is why Simmonds is often described by Murray and others as a two-way player.
While he has already passed his offensive totals from last season (nine goals and 14 points), Simmonds hasn't sacrificed the rest of his game.
He chases after loose pucks along the boards and in the corners. He is often the first to the forecheck and drops his gloves if necessary, despite being listed as 6 feet 2 and 183 pounds. He now often plays alongside center Michal Handzus on the third line, a partnership both say has consistently clicked because of constant communication.
"If you have a player who can play on the checking line and score many goals, I think it's incredible," Handzus said. "He's going to be a huge part of this club."
Yet, there are days Simmonds says he is still processing the fact he's actually playing in the NHL. He said Nov. 21 was an example. The Kings were playing host to Calgary, which meant Simmonds matched up against his idol, Jarome Iginla.
Then there was the time Simmonds teamed with Willie O'Ree, the NHL's first black player. Simmonds, who is also black, worked with O'Ree on the league's Hockey Is for Everyone program, an effort that included conducting clinics for kids.
Episodes like these leave Simmonds appreciative of his success, but it also propels him to keep working hard -- a recurring theme.
Murray said Simmonds' next step in the development process is to "continue to work hard -- there's no magic to it."
So far, that formula has worked.
"My parents stressed to me that you're going to have to work twice as hard as the next guy," Simmonds said. "I think I've learned to value everything that I've gotten."