Astros-Red Sox Preview

Fenway Park may be baseball's oldest stadium, but it will provide a possible glimpse into the future Sunday.

This series finale between the Boston Red Sox and Houston Astros features promising young rookie starters in 22-year-old Eduardo Rodriguez and 21-year-old Lance McCullers.

These pitchers were born six months apart in 1993, made their big-league debuts in May and are sporting 4-2 records. Boston's Rodriguez (3.92 ERA) is limiting opponents to a .216 average while Houston's McCullers (2.19) is holding foes to .187.

Sunday's edge could go to Houston (48-35) since Rodriguez has been tagged for 15 runs over 8 1-3 innings in dropping consecutive home outings. The left-hander was sharp Tuesday as he gave up one run in six innings to earn a 4-3 victory over Toronto.

That marked the fourth time in six starts he yielded one or no runs since making his debut May 28. The Red Sox (38-45) said he corrected a flaw from his previous outing in which he tipped his pitches.

"Working on it all those four days, on not tipping pitches to the hitters, working on it in my bullpen every time I throw the ball, that's why I did it better (Tuesday)," Rodriguez told MLB's official website.

McCullers is averaging 9.79 strikeouts per nine innings since he debuted May 18. He struck out six for the third straight outing Monday, allowing one run in seven innings to earn a 6-1 home win over Kansas City.

The right-hander, who posted a 2.11 ERA in June for the lowest by a Houston rookie in that month since Darryl Kile's 1.80 mark in 1991, credits a simple approach for his success.

"Attack the zone, pound the zone," McCullers said. "I stick with my game plan. Those guys are going to make adjustments, I'm going to make adjustments, but at the end of the day, I have to do what I'm going to do best."

Houston is playing without injured New England native George Springer and will receive a boost Sunday since outfielder Jake Marisnick will be activated after being out since June 18 with a left hamstring strain. Marisnick is hitting .245 with five homers, 20 RBIs and 11 steals.

Colby Rasmus struck out in all three at-bats in Saturday's 6-1 defeat in his return after missing six games due to a skin infection on his left wrist. He is expected to rest Sunday.

The Astros had a five-game win streak snapped as they managed six hits off Clay Buchholz, who pitched his first 2015 complete game.

Mookie Betts doubled twice and had three RBIs Saturday, making the Boston leadoff hitter 12 for 28 with seven RBIs during a six-game hitting streak. Xander Bogaerts was 2 for 4 to improve to .383 in his last 11 games and 8 for 14 in his last three.

"Mookie and Xander, particularly with men in scoring position, they're taking what the opposing pitcher is giving them," manager John Farrell said. "They're putting good swings on balls, using the whole field."

Shane Victorino went 2 for 4 in his first action since May 23 after being out with a strained left calf.