White Sox right-hander Reynaldo Lopez pitched much better than he felt Sunday.

Before leaving with dehydration and intestinal discomfort, Lopez threw five hitless innings in the Sox’ 2-0 victory against the Rangers. Not only did Lopez continue his second-half resurgence, but he also kept the young members of the Sox’ rotation on their upward trajectory.

‘‘We’re excited,’’ Lopez said through a translator. ‘‘This is a very, very exciting moment for all of us and for the organization. I think the expectations that you can have right now and that we have right now for the future are really, really high because we all know what we’re capable of doing.’’

After posting a 6.34 ERA before the All-Star break, Lopez needed a strong second half to keep himself in contention for a rotation spot in 2020. He has come through. After his abbreviated outing Sunday, Lopez is 4-3 with a 2.83 ERA since the break.

Lopez was effective despite an illness he said he had been battling for about three days. In fact, Lopez said he was quiet about it because he didn’t want to miss his turn in the rotation.

He started feeling especially bad in the third, but he was doing better after the game and a pair of IVs.

‘‘It is frustrating when things like that happen the day that you are pitching and through your outing, especially with an outing like today, where everything was going very well,’’ said Lopez, who threw a season-low 80 pitches. ‘‘I was kind of upset when I had to leave the game because I didn’t want to. I was feeling good . . . with my stuff. But physically I wasn’t doing well.’’

Lopez and the other members of the Sox’ rotation are doing quite well these days. As a group, their 2.80 ERA since Aug. 7 is the best in the American League.

Right-hander Lucas Giolito said his previous outing was ‘‘the best I’ve ever felt pitching in my life’’ and is burnishing his case for a strong finish in AL Cy Young Award voting. Meanwhile, right-hander Dylan Cease continues to grow every time he takes the mound. He showed it Friday, when he allowed three runs in the first but nothing after that.

That impressed Giolito, who said: ‘‘It looks like nothing’s really fazing [Cease] out there, which is a really cool trait to see from a young guy that just came up.

‘‘Giving up three runs in the first inning, then bouncing back and dominating from there, showing signs of growth. That’s part of the process, so it’s great.’’

Lopez said they have been learning every time they pitch. Perhaps just as important, the young pitchers are applying that knowledge.

‘‘I think you can see the results,’’ Lopez said. ‘‘For us as a group, it’s a very good moment. I think we have been working for this throughout the whole season. Right now is probably the best moment for us of the season.’’

Manager Rick Renteria echoed that. He said he also has seen growth as the season progresses.

‘‘It’s not necessarily the outcomes, even though you want those good outcomes to occur,’’ Renteria said. ‘‘It’s what they’re feeling in terms of what they believe they’re capable of doing in certain moments. They’re starting to trust themselves a little bit more and able to execute and get through games.’’