His stuff was electric. He was calm, cool, collected and composed.
Harvey is a 23-year-old former first-round selection and No. 7 overall pick by the Mets in the 2010 First-Year Player Draft. He attended the University of North Carolina at Chapel Hill.
While at North Carolina, Harvey dominated hitters, compiling a 27-7 record, and a 3.73 ERA in 238 2/3 innings. He struck out 263 batters in his collegiate career, which ranks ninth all-time among UNC pitchers.
Harvey dominated the D-backs with a deep repertoire of pitches that included two- and four-seam fastballs, a curve and a slider. He also threw an occasional changeup.
Putting it mildly, Harvey has a power arm and then some. He sat at the mid-to-high 90s in each of his 5 1/3 innings. When he left in the sixth, after issuing two of his three bases on balls, he was still bringing the heat at 95 mph.
It's one thing to throw a fastball with late life and great movement. It's quite another to mix in a devastating slider to keep a hitter off-balance and induce swings and misses.
That's exactly what Harvey did. He threw his slider down and in at the feet of hitters at velocities anywhere from 83-89 mph.
The hitter can sit on the fastball and then be completely fooled when the ball tails away out of the zone. That's what Harvey's slider did. Consistently.
Poised as if he didn't have a care in the world, Harvey used his 6-foot-4, 225-pound frame as an extra weapon. He threw downhill with a very easy, smooth and compact motion.
Remarkably, he showed another quality that made me realize his maturity belies his age.
Either by prearranged design or by his own volition, he did not shake off his catcher. Not once. He trusted recently promoted veteran receiver Rob Johnson. They had formed an outstanding battery at Buffalo this season.
One key to what I have observed with Harvey is his ability to repeat his delivery. He doesn't get out of sync. He doesn't try to overthrow. Rather, he stays within his capabilities and uses the same motion pitch after pitch. Until he tires. More about that later.
How many young pitchers control an outing by throwing first-pitch strikes? Not many. It isn't unusual for a young pitcher to scuffle a bit in early outings against the best hitters in the world. Not Harvey. He seemed to thrive in the moment.
Harvey showed the ability to command the strike zone and get ahead of almost every hitter he faced. He would then be able to dictate the repertoire and his pitch sequence for the remainder of the at-bat.
Again, I credit Johnson with having the skill and experience to shepherd and navigate his pitcher through the batting order.
In the rare times he fell behind in the count, Harvey was not shy about going to his breaking ball -- especially his slider. With three balls on a hitter, he could spot the slider away from the barrel of the bat and catch up in the count. That's a highly prized ability, even for the most-seasoned veteran pitcher.
As a highly rated player in the Mets system, Harvey compiled 245 2/3 innings pitched over parts of two seasons. He accumulated a composite 20-10 record in 46 starts.
Harvey had a combined ERA of 3.48 and a WHIP of only 1.29. It is no wonder the Mets were excited to promote him to the big club.
Showing almost the identical control he displayed in his Major League debut, Harvey walked an average of 3.5 hitters per nine innings in the Minor Leagues while striking out 8.1 per nine.
It would not surprise if Harvey dominated consistently as a starting pitcher.
It should also not be surprising that Harvey began to tire at the 90-pitch mark. In fact, I looked for signs of fatigue even earlier.
By the time the sixth inning rolled around, Harvey was beginning to elevate his pitches some and began missing the strike zone. Not alarmingly, but with enough frequency to cause the bullpen to get cranking.
Ultimately, he lost some of the control and command that effortlessly got him to that point of the game. He was replaced after his 106th pitch.
A little bonus for Harvey occurred when he helped his own cause by getting a couple of hits in the game. Pitchers don't forget such things. He'll probably be talking more about his prowess with the bat than his skill on the mound.
From what he displayed, he is the type of pitcher who at some point will climb his way to the top of the Mets' rotation.
Harvey can't be expected to fan 11 every outing, but he is capable of turning in a crisp, very well pitched game every start. He's the type of pitcher who can end a losing streak.
Mets fans can rejoice in the joy of having a pitcher who will help anchor the staff for years to come. He will bring a power arm, good command and a vast repertoire when he takes the mound. And a quality bat as well.