DETROIT -- Victor Martinez admits the Detroit Tigers have been weighed down by high expectations.

The star-laden club has slumped since the All-Star break, going 10-16 and losing four straight before its 8-4 victory over the Pittsburgh Pirates on Wednesday night at Comerica Park. Detroit remained a half-game behind Kansas City in the American League Central Division.

"When things aren't going your way, a lot of times we're trying to do too much," said Martinez, who had three hits and three RBIs as the designated hitter. "We've just got to relax, sit back and let this happen. You can't hit a three-run home run with nobody on. It's tough when everybody's struggling at the same time."

The Tigers' bats came alive to provide some hope of a turnaround. Along with Martinez's contributions, third baseman Nick Castellanos blasted a go-ahead home run and an RBI triple and catcher Alex Avila added a solo home run for Detroit (64-54).

"It's not fair when people out there are thinking we've got to win this division by 10, 15, 20 games," Martinez said. "Don't forget, we're playing major league baseball. We're not playing Little League teams."

Rookie Blaine Hardy (2-1) pitched two innings of scoreless relief for the victory. Hardy, who has been a rare bright spot in Detroit's shaky bullpen, lowered his ERA to 2.05 by making liberal use of his cut fastball.

"I didn't have a cutter last year," he said. "I went into the fall league and worked on it and it's been a big pitch for me."

Buck Farmer, a fifth-round selection in the 2013 draft, made his major league debut as Detroit's starter. Farmer, who was called up from Double-A Erie earlier in the day, allowed four runs on six hits. He struck out four in five innings while getting a no-decision.

"He did a good job," Pirates manager Clint Hurdle said of Farmer. "He mixed his breaking stuff, his changeup, more than we anticipated. That being said, he gave them five innings and we got four off him. Hardy was the guy who showed up big for them and gave them two solid innings of relief."

Left fielder Travis Snider hit a two-run home run for Pittsburgh (64-56). Pirates catcher Russell Martin had an RBI double for his 1,000th career hit, which also extended his hitting streak to 11 games.

Losing pitcher Vance Worley (5-2) gave up five runs, three earned, on nine hits in 5 1/3 innings as the Tigers rallied from a 4-1 deficit.

Detroit scored three runs in the fifth, aided by second baseman Jayson Nix's throwing error.

Castellanos, the third baseman, then smashed his ninth homer into the left-center field stands with one out in the sixth to give the Tigers a 5-4 lead. Detroit added three more runs in the seventh on Martinez's two-run single and right fielder Torii Hunter's fielder's choice grounder.

"It wasn't a sharp night for (Worley) overall but still, the three runs scored in the fifth inning, if we handled the ball a little better we could have gotten out of there with less," Hurdle said. "Some breaking balls were up tonight. This is a very good hitting ball club we're facing and you've got to make pitches."

Castellanos gave Detroit a 1-0 lead with a run-scoring triple in the second inning. Martin tied it with a two-out double in the third, driving in third baseman Josh Harrison, who also doubled.

Snider's third homer of the series highlighted Pittsburgh's three-run fourth inning.

Designated hitter Pedro Alvarez singled and scored on shortstop Jordy Mercer's triple before Snider ripped the next pitch into the right-field stands.

Detroit scored three runs in the fifth inning to tie it at 4. Avila led off with his 10th home run of the season. First baseman Miguel Cabrera's deep sacrifice fly after Nix's miscue and Martinez's single brought in the other runs.

NOTES: Tigers RHP Justin Verlander expressed relief Wednesday after an MRI on Tuesday showed no structural damage to his pitching shoulder. Verlander exited his start Monday against the Pirates with shoulder soreness after he allowed five runs in the first inning. "Obviously, you're kind of thinking the worst and hoping for the best," he said. "It seemed like I got the best news possible." ... Detroit optioned RHP Kevin Whelan to Triple-A Toledo to make room for Wednesday's starter, Buck Farmer. ... Pirates 3B/OF Josh Harrison led the majors with a .337 average as a leadoff hitter. "He's sparked us in a number of different ways," Pittsburgh manager Clint Hurdle said. ... Pittsburgh's 23-12 interleague record since last season is second in the majors behind Oakland's 23-9 mark. ... Tigers 1B Miguel Cabrera led the American League with 36 doubles despite not hitting one since July 19.