Keuchel and Smyly were both on the Arkansas team that reached the College World Series in 2009. Keuchel (3-2) allowed two runs and six hits in 7 2-3 innings.
Houston's George Springer, the 11th overall pick in the 2011 amateur draft, hit his first major league homer in the fifth and Jose Altuve put the Astros ahead 3-2 with a two-run double.
Carlos Corporan and Matt Dominguez also went deep for the Astros. Victor Martinez homered for the Tigers.
Smyly (2-2) gave up three runs and five hits in 5 1-3 innings.
INDIANS 9, TWINS 4
CLEVELAND (AP) — Asdrubal Cabrera had four hits and three RBIs, and Michael Brantley also homered as Cleveland stretched a winning streak to three for the first time season.
Cabrera, who entered hitting .215, had a solo homer in the second and RBI doubles in the seventh and eighth. He also singled in the fifth.
Justin Masterson (2-1) allowed four runs — two earned — four hits and four walks in 6 1-3 innings. Kevin Correia (1-4) gave up four runs, eight hits and four walks in 4 1-3 innings for the Twins.
Minnesota played its fourth straight game without first baseman Joe Mauer, who could be headed to the disabled list because of back spasms. Outfielder Sam Fuld was placed on the seven-day DL with concussion-like symptoms, leaving infielder Pedro Florimon as Minnesota's only bench player when the game began.
ORIOLES 3, RAYS 1
ST. PETERSBURG, Fla. (AP) — Steve Pearce hit a two-run homer, Ubaldo Jimenez won his second straight start and Baltimore completed a three-game sweep of Tampa Bay.
Pearce's second homer in three days came off David Price after J.J. Hardy's double in the second inning.
Playing first base in place of injured slugger Chris Davis, Pearce also made an outstanding stretch to catch a throw from Hardy that completed an inning-ending double play with the bases loaded in the fifth.
Rays manager Joe Maddon challenged the call, but the ruling that Pearce had kept his foot on the bag was confirmed after a 2-minute review.
Nick Markakis extended his hitting streak to 15 games with a single in the third.
MARINERS 1, ROYALS 0
SEATTLE (AP) — Hisashi Iwakuma scattered four hits over eight innings and Corey Hart hit an RBI single to lift the Mariners, who won for the 11th time in 14 games since losing eight straight from April 15-22.
Iwakuma (2-0) was making his second start after beginning the season on the disabled list with a strained tendon on the middle finger of his pitching hand. The All-Star right-hander struck out seven and walked none.
Fernando Rodney worked around two walks in the ninth to earn his 10th save in 11 chances.
Danny Duffy (1-3) gave up one run and two hits in six-plus innings. He has allowed two hits and a run in each of his first two starts this season after pitching out of the bullpen to begin the year.
BLUE JAYS 12, PHILLIES 6
TORONTO (AP) — Edwin Encarnacion hit two of Toronto's five home runs and the Blue Jays won their eighth consecutive game against Philadelphia.
Juan Francisco, Adam Lind and Colby Rasmus also went deep to help Toronto extend its winning streak to a season-best five games. Encarnacion hit a leadoff shot in the second inning against A.J. Burnett and added a two-run drive off Luis Garcia in the seventh for his 12th career multihomer game.
Francisco followed Encarnacion's second home run with a shot to centre field, his second in two days, as the Blue Jays went back-to-back for the first time this season.
RANGERS 5, ROCKIES 0
ARLINGTON, Texas (AP) — Prince Fielder homered, Matt Harrison earned his first win of the season and Texas beat Colorado after being overwhelmed by the Rockies the previous three games.
Harrison (1-0) and four relievers combined on a five-hitter, the Rangers' major league-best seventh shutout. Joakim Soria worked a perfect ninth with two strikeouts.
Rockies third baseman Nolan Arenado extended his hitting streak to 28 games with a single in the third. That broke the team record he matched Wednesday night.
Colorado came in as the only National League team without a shutout loss. The Rockies, whose 22 wins are tied for most in the majors, had 50 hits and outscored the Rangers 29-5 the previous three nights — the first two in Denver before the interleague matchup switched to Texas.
CUBS 12, WHITE SOX 5
CHICAGO (AP) — Anthony Rizzo, Starlin Castro and Mike Olt homered, and the Cubs stopped a four-game slide.
Rizzo had three hits and scored three times as the Cubs salvaged the finale of the city series. Olt, Ryan Kalish, Nate Schierholtz and Junior Lake had two hits apiece in a game that took 4 hours, 7 minutes.
The Cubs put it away with five runs in the eighth, highlighted by Olt's first career grand slam. Maikel Cleto also hit Welington Castillo with a pitch with the bases loaded, ending the White Sox bullpen's shutout streak at 23 1-3 innings.
The Cubs finished with 15 hits after managing just five runs and 12 hits in the first three games against the White Sox.