In what has to be the early-career highlight for Tanner Houck, the Boston Red Sox’s 2017 first-round draft pick went up against the American League’s 2015 Cy Young Award winner in Dallas Keuchel. The Houston Astros ace was pitching in what the team hopes is his last rehab assignment before rejoining the Astros, currently on the road in Baltimore.

The Lowell (Mass.) Spinners, short season affiliate of the Red Sox, hosted one of the best pitchers in baseball Saturday night (July 22). Keuchel started for the Tri-City ValleyCats, the Astros’ short season affiliate in the New York-Penn League.

Keuchel said that this second rehab start is more about building his arm stamina.

“I always try to go up and down more than pitch counts,” he said recently. “I’d like to do four or five innings. That’ll set me up for maybe five, six in the first start back (with Houston).”

Related: Keuchel Pitches for Double-A Corpus Christi in First Rehab Start

Keuchel last pitched June 2 against the Texas Rangers, and has put up a 9-0 record with a 1.67 ERA prior to his injury. He was previously listed on the 10-day disabled list due to a nerve issue in his neck. In addition to his Cy Young award, he is a two-time All-Star and three-time Gold Glove recipient.

Interestingly, Saturday’s game wasn’t the first time Keuchel pitched at LeLacheur Park. In 2009, he made his professional debut with Tri-City in Lowell, thus bringing him back to where his already accomplished career began. This night, Keuchel was pitching in cloudy, 84-degree weather.

“It’s a little rare for guys to rehab at that level, but, given we were going to be in the Northeast here in Baltimore and we go to Philly after that, it was certainly the most convenient,” Houston manager A.J. Hinch said Friday about Keuchel’s assignment. “He will get a taste of another level, increase his pitch count, hopefully his inning count and get closer to being back here.”

Houck made just the second start of his career for the Spinners. The University of Missouri product made his professional debut July 17, and threw one inning of work, striking out two and allowing a pair of earned runs.

In the Spinners’ first frame, Keuchel got the first two batters to ground out, the second on a come-backer, and he caught the third batter looking for his first K of the game.

Curiously, and apparently on a very short leash, Houck was relieved early in the 2nd inning, after facing only 7 batters and allowing a hit, a walk, and an earned run. He did hit a batter, and only half of his 34 pitches were strikes in his 1.1 IP.

In the Spinners’ 2nd, the first batter managed a single, but Keuchel retired the side with a fly out, groundout, and a swinging K. After two innings, Keuchel had thrown almost nothing but strikes, with 18 of his 21 pitches (86%) being over the plate.

Meanwhile, Keuchel’s ValleyCats teammates had spotted him a 2-0 lead going into the bottom of the third, in which Keuchel again, laser-focused, bedazzled the Spinners with strikes. Two groundouts sandwiched around a pop out was all Lowell could muster. After 3, Keuchel had thrown 26 of his 30 pitches over the plate (87%)!

Ironically, the 4th inning started with a hit batter by Keuchel. Regrouping, the lefty proceeded to coax a groundout and two swinging strikeouts to end the inning. Pitch update after four: 38 of 49 pitches for strikes (78%).

After a strikeout to start the 5th inning, Keuchel gave up a run on a double and an RBI single, ending the inning on successive groundouts. 2-1, Cats over the Spinners, after 5, and thus ended Keuchel’s evening.

Keuchel totaled 5 strikeouts for the game, and true to form, induced eight groundouts to just one fly out in his 19 batters faced. Forty-eight of his 62 pitches were over the plate (77%).

Keuchel’s game plan going in seemed to be just focusing on getting the ball over the plate, even if it meant fat over the plate, as most of his pitches seemed to be nowhere near corners. His goal seemed to be to just let them hit it, see how the neck feels, and return to the Houston rotation, hitting his corners then.

As his pinched nerve issues shouldn’t need a next-day recovery assessment, and a pain-free outing was hoped for, it’s possible this outing may point Keuchel to rejoining the Houston staff for a start in Detroit at the end of July.

“I hope this will be his last rehab start,” Hinch said. “I know he’s feeling really good. We want to make sure that he feels as good as he did last time this next time. If that’s the case, we will certainly consider this being his last time. He’s itching to get back at this level.”