“It’s looking like he’s a front-line kind of guy for any team, not just our team,” catcher Matt Thaiss said.

CLEVELAND — It’s not often you see Guardians outfielder Steven Kwan strike out.

Kwan is one of the best contact hitters in the game, with excellent plate vision and superb bat-to-ball skills. To strike out Kwan, it takes a mix of velocity, command and deception.

That’s why it was notable when White Sox starter Shane Smith got Kwan to whiff on an 89.7 mph changeup outside the zone in the fourth inning of the Sox’ 1-0 walk-off loss Tuesday, their sixth defeat in a row.

‘‘It’s looking like he’s a front-line guy for any team, not just our team,’’ catcher Matt Thaiss said.

Kwan struck out at the second-lowest rate in the majors among qualified hitters last season (9.4%), according to FanGraphs.

Smith, a Rule 5 draft pick, pitched six scoreless innings, allowing two hits and one walk and striking out six. But the Sox’ offense undermined Smith’s outing by supplying only two hits and going 1-for-8 with runners in scoring position.

In the ninth, reliever Mike Clevinger allowed a leadoff single followed by three walks, walking in the winning run.

‘‘We just haven’t strung it together enough,’’ Thaiss said. ‘‘We’ve got a lot of guys putting up good at-bats, and they’re spread out right now. At some point, we’re going to get [hits] in a row, and we’ll put up five, six, seven [runs] in an inning, like we did early on in the season.’’

Smith was excellent in his second major-league start. He didn’t allow his first hit until the sixth, when Guardians star Jose Ramirez reached on a softly hit ball toward third base.

Smith thrived despite facing a lefty-heavy, patient Guardians lineup on a 35-degree day at Progressive Field. It was the second-lowest temperature for a home opener at the ballpark.

‘‘We saw the fastball being dominant in the first game,’’ manager Will Venable said of Smith. ‘‘Just a good job with the changeup this time. It was nasty, filling up the zone and really mixing it up.’’

Smith became the second Sox starter to pitch six or more scoreless innings with two or fewer hits allowed in his second career start since Wilson Alvarez in 1991.

Part of Smith’s development is figuring out how to work without his best stuff and around traffic in pivotal moments. With runners on first and third and two outs in the sixth, he struck out designated hitter Kyle Manzardo, who fouled off two changeups in the zone before whiffing on a curveball.

‘‘We only threw him one [curveball] in the first at-bat, and that was just the pitch that was working at the time,’’ Smith said. ‘‘Especially in a tight jam right there, just lean on the curveball.

‘‘I knew my day was probably close to over at that point. I just wanted to make a really good pitch at the time I needed it, and I did.’’

After Smith surprised the Sox with his performance in spring training, it was going to be interesting to see whether he could carry his success into the regular season. So far, the results have been encouraging.

‘‘He stayed composed all the time,’’ Thaiss said. ‘‘He couldn’t tell what situation he was in. You could see he was ready for it. He made a huge pitch with the game on the line.’’