CLEVELAND -- The Astros were gathered in the visiting clubhouse at Progressive Field about three hours before Wednesday’s game against the Indians, minutes before the 4 p.m. ET Trade Deadline hit. They were refreshing their phones and staring at the TVs, eager to find out the latest trade news. Some, like Justin Verlander, tweeted about the anticipation.

Astros manager AJ Hinch, sitting on pins and needles all afternoon, finally got the word from president of baseball operations and general manager Jeff Luhnow that Houston had landed right-hander Zack Greinke and cash in a blockbuster deal with Arizona. His goal was to be the first to share the news with the players before they saw it on social media, which meant making a quick dash to the clubhouse.

News was trickling out, but Hinch turned off the TVs and announced a move that entrenches Houston as MLB's World Series favorite.

“There was some hooting and hollering,” said right-hander Gerrit Cole, who is a friend of Greinke. “It was like 4:08, I think, is when it broke and AJ came in with a [huge] smile. We were very excited.”

The Astros pulled off four trades on Wednesday, none bigger than the Deadline-busting deal to acquire the six-time All-Star and former American League Cy Young Award winner Greinke, who will join Verlander, Cole and Wade Miley atop Houston’s built-for-October rotation.

“Incredible day for the organization and our team,” Hinch said. “The energy in our room after a thing like that happens is palpable. You know that what you have in front of you is one of the greatest opportunities to keep the winning ways alive.”

According to Baseball-Reference.com, Greinke gives the Astros four starting pitchers with an ERA+ of more than 140 for the first time since the 1907 Cubs. Greinke threw five innings of two-run ball at Yankee Stadium earlier on Wednesday before the trade.

“For us,” Luhnow said, "Zack Greinke was at the very top of our list in terms of players that we thought could impact our chances to win the World Series this year and could really fit in well on this club for the next couple of years while we still have our entire offensive unit together."

Luhnow said he didn’t contact the D-backs until the final 48 hours prior to the Deadline. The deal was finalized inside the final two minutes before the Deadline after the Astros' front office got comfortable with the haul of players heading to Arizona, as well as owner Jim Crane signing off on the financial commitment. Greinke is due $70 million over the next two seasons of his contract, which runs through 2021. The D-backs will pay about a third of his remaining salary, according to multiple reports.

“A little reminiscent of the [Verlander] deal [in 2017], and obviously, with a hard deadline this year, it was important we get something done,” Luhnow said

The Astros also acquired starting pitcher Aaron Sanchez, reliever Joe Biagini and Minor League outfielder Cal Stevenson in a trade with the Blue Jays, as well as veteran catcher Martin Maldonado from the Cubs in exchange for Tony Kemp. The Astros also sent catcher Max Stassi to the Angels for Minor League outfielders Rainier Rivas and Raider Uceta.

The trade for Greinke came at a high cost for Houston, though, which gave up three of its top five prospects according to MLB Pipeline: first baseman Seth Beer (No. 3) and right-handers J.B. Bukauskas (No. 4) and Corbin Martin (No. 5), in addition to infielder Josh Rojas (No. 22) and cash going to Arizona. Martin recently had Tommy John surgery and is out for the season.

“We gave up four legitimate prospects that we were very excited about,” Luhnow said. “To get a future Hall of Famer like Zack Greinke on our team for the next 2 1/2 years, we had to give up a lot of value, and it was painful. That’s why it took so long. We were really resisting giving up all four of those guys and tried different permutations and different replacements, but at the end of the day, that’s the deal they insisted on and that’s the only deal that was going to get done. We ended up conceding at the last moment.”

Greinke, 35, is 10-4 with a 2.90 ERA in 23 starts with the D-backs and has been one of the premier starters in the game for more than a decade. He’s won 197 games in his career with a 3.36 ERA and won the 2009 AL Cy Young Award with the Royals.

“As a pitcher, I’ve watched him and tried to learn from him every opportunity I can,” Cole said. “I think he’s a Hall of Famer and I think he’s one of the best pitchers of our generation. Just really a true craftsman in the sense of always evolving, always being forward-thinking. His preparation is off the charts. Durability. Competitiveness. What a pickup.

"They nailed it.”

Greinke will team with Verlander (14-4, 2.73 ERA), Cole (12-5, 2.95 ERA) and Miley (9-4, 3.06 ERA) to give the Astros arguably the deepest rotation in the Majors to go along with one of the league's most potent lineups. It’s clear the Astros are pushing all their chips in to make a run at another title.

“We acquired him because of how good he is and we expect him to be a big part of our push to win the division and keep winning into October,” Hinch said. “Look, the reason we got him is we feel like we can have one of, if not the best, rotation in baseball. He’s in the top five in WHIP, he’s low ERA, he’s hard to hit, he defends his position, he’s elite across the board. Adding him to any rotation is a positive; adding him to this rotation is pretty incredible.”

Still, the Astros were able to hold onto top prospect, outfielder Kyle Tucker, who remains a big part of the Astros' future plans. Luhnow told teams Tucker and top pitching prospect Forrest Whitley were untouchable as part of any deal.