DENVER -- Rockies rookie Ryan Castellani has shown in two starts that he has the pitches to compete with Major League hitters. His next step will be to ration his pitches so he can last deeper in games.

Friday night, before exhausting his pitch count, Castellani struck out seven and held the Rangers to one run on two hits in 4 2/3 innings of the Rockies’ 3-2 loss at Coors Field.

• Box score

Castellani settled for the fate of being an impressive freshman who could only watch as Rangers veteran Lance Lynn spent a complete game teaching a master class.

Lynn, who also vanquished the Rockies in a 1-0 victory on Opening Day, limited the Rockies -- who for the most part have been playing high-scoring games at home -- to two hits, two runs (one earned), six strikeouts and no walks as he lowered his ERA to 1.11. A scratched-out run off Daniel Bard -- it scored when Bard induced a double play -- was the difference.

“The goal for all pitchers is, obviously, command of the strike zone -- a great example is watching the other guy pitch tonight,” Rockies manager Bud Black said. “Pound the strike zone, a very good ball-strike ratio, no walks and was on the attack. With Ryan, he was on the attack. He’s aggressive. I like that.”

Castellani -- who threw four hitless innings at Seattle on Saturday in his Major League debut -- left one key area for improvement. When he was removed after walking No. 9 hitter Jeff Mathis, Castellani was at 88 pitches. Lynn needed 110 to complete nine innings.

Overall, Castellani -- the Rockies’ No. 18 prospect -- earned high marks, and he left with a thirst for more.

“Me and Tony [Wolters, his catcher] used all four pitches really well,” Castellani said. “We didn’t wait. In the first inning, we had our plan. We executed it. Breaking balls in the zone were great, slider and curveball. We used the changeup when we needed to. We got a little bit behind with the fastball early on, but we were able to finish some guys.”

The full pitch mix -- which earned him the callup from the Rockies’ alternate training site after Chi Chi González’s right biceps strain -- controlled every Rangers bat except the one swung by Nick Solak, who doubled in the second and lined an opposite-field homer to right on the first pitch of the fifth. Castellani had 57 strikes on his 88 pitches and earned praise from both sides.

“He showed a lot of confidence,” Rockies shortstop Trevor Story said. “He’s a competitor, and he’s out there showing it. He’s definitely not scared. The moment’s definitely not too big for him. He’s just going out there and letting it eat.”

Rangers manager Chris Woodward said: “The kid looked good. He used his curveball when he was behind in the count, and his fastball when not expected. I thought he did a good job using all his pitches. He threw the ball well."

The pitch counts in his first two outings -- from 60 at Seattle to 88 Friday -- show the gradual buildup expected, because Castellani didn’t begin the year on the active roster. And a look at the Rangers’ hitting plan revealed hitting strategies that are hard to simulate in a camp full of players whose main goal is to be ready in case the big club calls.

Castellani fell behind, 3-0, to leadoff man Shin-Soo Choo in the first inning, and the first time through the order he dropped behind four other hitters, 2-0, and just two of the nine swung at the first pitch. Castellani, to his credit, needed to use his repertoire to work back into counts. But those pitches, and the pitches needed to put away strikeouts, increased his limited count.

“Fine-tuning his command is the next step,” Black said. “Big league hitters have a little more discernible eye. They don’t chase as much as Minor League hitters.”

But at some point they were going to fire early. Solak, who had not homered this season, fired at a first-pitch changeup that was down but over the middle. The ball just cleared the tall right-field wall.

“I’m not going to beat myself up too much about it, but he is a guy that is going to ambush, and he did exactly what he needed to do -- and it got up just enough,” Castellani said. “I would love to have that one back but it wasn't too poorly executed.

“But that second third time through, those guys showed us that they were going to ambush. I just got to make a little better pitch.”