LOWELL -- The last time Boston Red Sox top pitching prospect Jason Groome started a game, it did not go so well. The former No. 12 overall draft pick struggled on April 10 with high-A Greenville, allowing nine runs on seven hits and three walks through 1 1/3 innings before leaving with a lat injury.

Over two months later, Groome took the mound again Monday night with the Class-A Lowell Spinners, and his outing was a short one again. This time, however, he was quite impressive until the rain suspended his game.

Groome pitched 2 1/3 scoreless innings while striking out three, walking one and allowing one hit -- an infield single. He finished having thrown just 38 pitches -- 24 of which were strikes. It was a welcome return for the 18-year-old, who was pitching on a rehab assignment on Lowell's opening night.

"I felt great," Groome said. "I was ready to get back out and pitch against real competition. And then the rain kind of brought my attitude down a little bit. But like I said, I was ready to go as soon as I started throwing in the bullpen."

Groome's fastball velocity spanned from 89 mph to 94 mph, though it sat around 91 mph. His curveball was between 74 and 78 mph, while his changeup was between 80 and 83 mph. Two of his strikeouts came on curveballs, while one came on a fastball.

Perhaps the most impressive part of Groome's outing was his ability to hit his locations on his off-speed pitches. Groome noted that he has been working hard on his changeup since before the season began, and both of his off-speed pitches seemed to be working well Monday night.

"Just being able to have the command on his pitches is huge," Lowell manager Iggy Suarez said. "Obviously he has a high ceiling with his talent and what he can bring to the table. Being able to get him that at a young age along with his mindset and his makeup makes it even better."

Another key part of the outing was that Groome came out of it healthy. He is looking to get back to Greenville, which just clinched the first half title, as soon as possible. As of Monday, he had no issues with his lat injury.

"I feel like myself again," Groome said. "Like I said the other day, I couldn't be more happy to just be throwing pain-free and just get back out there. It was some kind of muscle -- I don't even know. I just knew I had to go hard in rehab to get it better and that's what I did. I didn't really pay too much attention to what the injury was. I was just trusting my trainers and what they had me doing and it paid off."

Monday's outing was just Groome's fifth start since being drafted by the Red Sox, and it's something Boston would like to see more of. Even at a young age, Groome is showing maturity both on and off the mound in the minors.

"Good kid," Suarez said. "That's good to see that in a high draft pick so young. You would think (he'd show) immaturity, but you would think he's a college guy and he's got some years under his belt and he carries himself very even-keel as well. Just to see him on the field is impressive to see the way he acts."

Groome is ranked as the No. 2 prospect in the Red Sox system by both soxprospects.com and mlb.com, and for good reason. Still, at 18 years old, he won't be getting the call-up to the big leagues any time soon. According to Groome, his prospect ranking isn't something he pays attention to -- at least not all the time.

"I really don't look at what people write -- Well, at least not the bad stuff. The good stuff I read," Groome said with a laugh. "I'm ranked for a reason and everyone knows that, so I just go out there and keep doing what I do and it speaks for itself."