TAMPA – When Lightning GM Steve Yzerman arrived at Amalie Arena for work early Monday morning, he still had no idea what, if anything, he'd be able to accomplish by the 3 p.m. trade deadline.

The Hall of Famer had tirelessly tried to bolster his blueline without paying "outlandish prices." Yzerman kicked the tires on Senators star Erik Karlsson, which required a "big deal," as well as other desired targets. "We gave it our best shot," Yzerman said.

Yzerman said Rangers captain Ryan McDonagh was near the top of their list, but he hadn't heard from New York in a couple of days.

"It was really, really quiet," Yzerman said. "I just kind of sat and waited."

And then Yzerman struck.

The Lightning acquired McDonagh, 28, and forward J.T. Miller in a blockbuster trade with the Rangers. Tampa Bay had to pay a hefty price, dealing 20-goal scorer Vladislav Namestnikov, touted prospects Brett Howden and Libor Hajek, a first-round pick in June and a conditional first-rounder in 2019.

"We felt we gave up a lot," Yzerman said.

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But what the Lightning got was a top-four shutdown defenseman in McDonagh, giving it a better shot at making a Stanley Cup run. And McDonagh is under contract at $4.7 million through next season, so Tampa Bay could have two cracks at it.

"If we stood pat, are we winning the Cup? I can't tell you," Yzerman said. "But I can't tell you we weren't, either. I think we're a better team than prior to making the move. It's hard to say our defense isn't better. Does that guarantee we will win the Cup? It doesn't. It gives us a better shot."

The Lightning might not have been able to reel in the big fish in Karlsson, but McDonagh could be the better fit. A left-shot, McDonagh is a dynamic two-way defenseman, a strong skater who can play on both the power play and penalty kill, not to mention a proven playoff performer.

"A very good shutdown d-man," said former Rangers teammate Dan Girardi.

Said fellow former Ranger Anton Stralman: "One of the more solid d-men out there."

McDonagh, a Ranger the past eight seasons, said he could see this one coming after New York management sent a letter to fans a few weeks ago saying they were going to rebuild. And McDonagh, who had a 10-team no-trade list, got excited by the chance to play for a contender.

"They're a top team in the league now and have been for a long time," McDonagh said. "Especially this season, there's some big expectations there and I hope to help be a part of."

McDonagh, who has been sidelined with an upper-body injury, said he's about 5-7 days from returning, maybe by the March 8 game against the Rangers?

McDonagh said the deal was "sweeter" knowing Miller was joining him. Miller, 24, brings size (6 feet 1, 218 pounds), versatility (can play center or wing) and proficiency on faceoffs (53 percent), which should boost one of the worst teams in the league in the dot.

Yzerman said Miller's name came up in conversation with Rangers GM Jeff Gorton on Monday morning, and he inquired how he might get him. Gorton brought up Namestnikov, a former first-round pick who is having a career year.

Yzerman said last week he didn't want to deal from his current roster, but to get something good, you have to give up something. Namestnikov might have priced himself out of Tampa Bay this summer, when he's a restricted free agent with arbitration rights.

"I want to thank Steve Yzerman, teammates and staff for all the good times and memories, and our Tampa Bay Lightning fans for unconditional love and support," Namestnikov tweeted. "I'm excited for the next chapter in my career."

The Lightning would have likely had to give up much more to land Karlsson, who ended up not getting dealt. Tampa Bay didn't have to lose the likes of defense prospect Cal Foote or Taylor Raddysh, and it still has a deep farm system, even without Howden and Hajek.

"No difference maker in that group," said former NHL GM Craig Button, TSN's director of scouting. "Howden is a solid hard-working player. Hajek is a solid type 'D' who is not a top 3 IMO."

With McDonagh, the Lightning has a surplus of nine defensemen. Yzerman said the team plans to keep them all for now. Tampa Bay would have likely lost Andrej Sustr, Slater Koekkoek or Jake Dotchin if it tried to send them down.

"We can fit it into our cap, roster isn't an issue right now," Yzerman said. "We've got a better defensive core."

Especially now with McDonagh.

Joe Smith can be reached at joesmith@tampabay.com. Follow @TBTimes_JSmith.