Gray, selected third overall last week out of Oklahoma, arrived in Denver on Tuesday and the sides completed the contract a day later. He attended a news conference at the ballpark before Colorado played the Washington Nationals, shook hands with star shortstop Troy Tulowitzki and in the middle of the third inning was introduced to the crowd on the video board, answering a rousing welcome with a smile and a wave.
"Pretty crazy," Gray said. "It still hasn't hit me yet."
Gray said he was glad the deal was done so he could turn his attention to beginning his professional career. He is the highest 2013 draft pick to sign so far—the right-hander was chosen after Stanford pitcher Mark Appel (Houston Astros) and San Diego third baseman Kris Bryant (Chicago Cubs).
"It feels great. A huge relief, and I'm ready as soon as possible to go out and play," Gray said.
He will join the Rockies' rookie league team in Grand Junction.
Baseball America reported that Gray received a $4.8 million signing bonus, below the assigned slot value of about $5.6 million but still a record for the Rockies. Their previous high was $3.9 million given to left-hander Tyler Matzek in 2009.
A power pitcher whose fastball clocks consistently in the mid-to-upper 90s (mph) and has occasionally hit 100 mph, Gray was an appealing pick for the Rockies. Though he probably won't pitch at Coors Field for some time, he said he's well aware of its reputation as a hitter's paradise.
"I hear the ball flies here," Gray said. "It's not a pitcher-friendly ballpark. But that's something I'll learn to overcome. As I work through the system, I'll be able to do that."
He certainly has shown plenty of promise.
As a junior this season, Gray went 10-3 with a 1.64 ERA and 147 strikeouts in 126 1-3 innings. He was a first-team All-American and a unanimous all-Big 12 Conference selection.
"Jonathan has a power arm and he is a great competitor," Bill Schmidt, Colorado's vice president of scouting, said last week after the club picked Gray. "Jonathan is a good kid who we feel has a chance to be a quality starting major league pitcher."
In the days before the draft, published reports cited unidentified sources who said Gray tested positive for the medication Adderall during baseball's predraft drug-testing program. Gray and the Rockies have declined to comment.
A native of Shawnee, Okla., Gray was drafted by Kansas City in 2010 (13th round) and the New York Yankees in 2011 (10th round), but wasn't ready to sign and went to school instead. He attended Eastern Oklahoma State College in 2011—going 6-2 with a 2.89 ERA—before transferring to Oklahoma in 2012.
Gray said he kept working on his craft, polishing his pitching skills in hopes of improving his stock.
"I kind of took that as a challenge," he said. "I knew I could put myself somewhere in the top picks if I just applied everything and worked toward that."
His approach paid off.
"Now that it's done, I feel great about it. I don't think there's a place I could feel better in," Gray said.