Horton exits 2nd start after 17 pitches with right forearm discomfort

CLEVELAND -- Cubs righty Cade Horton fired a fastball to Bo Naylor on Friday evening and immediately looked in the direction of the visitors’ dugout at Progressive Field. A moment later, catcher Carson Kelly was up out of the crouch and heading to the mound.

Horton represents one of the main reasons Chicago has so much faith in its rotation this season, so his early exit in Friday’s 4-1 loss to the Guardians was cause for concern. The Cubs announced that Horton exited with right forearm discomfort, which limited him to four batters and 17 pitches into his second start of the season.

After retiring the side in order in the first inning, the 24-year-old Horton led off the second with a walk to Cleveland’s Kyle Manzardo. He followed that with a curveball for a ball to Naylor and then sent a 93.8 mph fastball low in the zone for a strike. That was when Horton looked to the dugout and was soon in a discussion with manager Craig Counsell and head athletic trainer Nick Frangella.

Horton was then lifted from the game -- replaced by veteran righty Colin Rea.

Early last season, Rea stepped into the rotation in April following a season-ending elbow injury for lefty Justin Steele. Once again, Rea began this year as part of the bullpen, giving Chicago experienced depth in case anything went awry with the rotation. After taking over for Horton on Friday, the right-hander gave Chicago 3 1/3 innings of solid work, limiting the Guardians to one run.

That last fastball from Horton was a noticeable drop in pitch speed not only from his season average (95.4 mph, per Statcast), but also a swift decline from the first inning. The righty was sitting between 95.5 mph and 96.5 mph in the opening frame (10 pitches). Horton threw five fastballs in the second with his last three declining in velocity (95.4 mph, 94.2 mph and 93.8 mph) prior to being pulled.

Last season, Horton finished as the runner-up in balloting for the National League Rookie of the Year Award after going 11-4 with a 2.67 ERA and 97 strikeouts versus 33 walks in 118 innings (23 appearances). That included posting a tidy 1.03 ERA in a dozen starts after the All-Star break.

Horton opened this season as the Cubs’ No. 2 starter behind veteran lefty Matthew Boyd and the righty was solid in his season debut. Horton limited the Nationals to two runs over 6 1/3 innings in his first outing of the year on Saturday at Wrigley Field.