"You kind of tell yourself that you're not going to believe it till it actually happens," Stamkos said.
When it actually happened hours before the trade deadline, St. Louis got his wish to leave and join the New York Rangers and the Lightning's season took another crazy turn with the addition of Ryan Callahan.
Tampa Bay's first game without St. Louis and with Callahan was also the first one Stamkos played since breaking his right leg four months earlier. As the 24-year-old made his long-awaited return March 6, the captain's "C" was on his chest as coach Jon Cooper's team began a new era, led by the face of the franchise.
"This past month's been the changing of the guard," Cooper said Wednesday. "It's been tough on him because he's trying to get his game back in order and for a guy that has missed 50 games or whatever it was, he just jumps right into a playoff push and he's trying to lead our team. I just can't say enough about what he's done to keep us all together."
Since returning, Stamkos has had to balance rounding his game back into form after missing 45 games along with taking on added responsibilities replacing St. Louis as captain and adjusting to new linemates. That's a lot to juggle, even for one of the NHL's most talented and mature stars.
"It's been pretty crazy," he said. "Coming back and getting all excited and obviously the trade deadline happening and being named captain and the expectations I put on myself to come back and produce right away and help this team win."
On the ice, Stamkos knows it will take time to get everything back the way it was when he was leading the Lightning in scoring and was on pace for a 50-plus-goal season.
That starts in his own head and with his body, after going through exhaustive rehab to repair the broken right tibia from crashing into the net Nov. 11 in Boston.
"When you're out for a long time, you expect to come back and feel the same. Realistically you've missed four months," Stamkos said. "With a leg injury that definitely affects your skating. I still don't feel like it's where I want it to be, but it's going to take a lot more hard work and probably a summer of training to get that strength back."
Through a half-dozen games, Stamkos feels that strength slowly coming back. Cooper sees it from the bench, too.
"His heart's still there, he's getting his lungs back but his timing, that's a little bit off right now," Cooper said. "But I'll be honest, he's electrifying every time he's on the ice. He'll be the first one to tell you there's still holes in his game right now, but with each one you just see him getting better, better and better. It's coming at no better time than right now because we need him."
Stamkos had two goals and two assists in his first six games back in the lineup, and the Lighting are 3-1-2. Along the way. he has had to adjust to new linemates in Alex Killorn and Tyler Johnson after playing with St. Louis for pretty much his entire time in Tampa up to this point.
"When you're so used to playing with one player your whole career, tendencies and chemistry, you take that for granted a little bit," Stamkos said. "You have to go over video, you have to communicate. I think that's the biggest thing. And we've done a pretty good job of that. It's not going to happen overnight."
One thing that did happen overnight was Callahan fitting in seamlessly. The former Rangers captain had a goal and three assists in his first six games with the Lightning, but perhaps more importantly brought some sandpaper and grease that had been missing from a team built on youth and speed.
"He's just brought a different dynamic to our team," Cooper said. "That kid knows how to play the game below the dots, and we just haven't had a ton of those guys wheel through our organization."
Cooper can see what Callahan means to the Lightning whenever he hits someone, forces a turnover or battles in front of the net. The whole team notices.
"Guys are just pumped for him," Cooper said. "It's great to see because he doesn't get to see that, obviously — he's in the corner battling (six-foot-nine Boston Bruins defenceman Zdeno) Chara, so he doesn't really hear what's going on. But it's great to hear, you love that from your team and teammates when you hear that stuff."
Callahan may be an effective second-line catalyst for the Lightning, but if they're to keep it up to make the playoffs and perhaps make a bit of a run, it'll be largely on the shoulders of Stamkos.
While Stamkos was out, St. Louis shouldered the load and would've been an MVP candidate if not for his trade request that followed Tampa Bay GM Steve Yzerman and Team Canada leaving the 38-year-old off the original Sochi Olympic roster and other prior issues that made him want out.
Beyond the St. Louis situation, the Olympics represented adversity for Stamkos, too, as he wasn't cleared to play and had to withdraw just a few days before players left for Russia. The Markham, Ont., native only watched a couple of games, including his Canadian teammates beating Sweden to win the gold.
"It was bittersweet," he said. "Obviously a proud Canadian and watching the way they played and dominated over there, but at the same time knowing you could've been there possibly bringing home a gold medal and not knowing what the future holds, it was a little difficult.
"But that's the way it is. I can't change anything now. I think we did absolutely the right thing by not going and having those 2 1/2 weeks to get back and get ready for most importantly the Tampa Bay Lightning and this playoff run we're in."
Stamkos is still in the process of getting ready as the season winds down. But amid all the adjustments he has had to make since he returned and St. Louis was traded, taking on the captaincy was the least of them.
"I don't think it changes the way I go about doing my business," Stamkos said. "Obviously it's not the way I envisioned being captain of the team. Under the circumstances, I definitely want to be the guy that the guys can lean on and trust."
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