Marty Brown didn’t hesitate to make the comparison again Sunday. Brown was managing in Buffalo in 2004 when Grady Sizemore continued his ascension up the Indians’ farm system. He was 21 years old and already considered a can’t-miss center fielder when he spent a season with the Bisons.

Sizemore, if you remember, had an abundance of talent with his speed and range in the outfield. He had a strong arm and was a complete hitter. Nearly a third of his 120 hits nine years ago were for extra bases, including eight homers. He could steal bases. His greatest strength, however, was his ability to compete. Anthony Gose is blessed with everything Sizemore had and more. If anything, perhaps he was born with too much talent. He hasn’t been through enough batting slumps to understand how to crawl out of them. He hasn’t learned the importance of getting the most out of each plate appearance regardless of the outcome.

He has had little experience in overcoming failure.

“It’s harder for Anthony than it was for Grady, but the talent is off the charts,” Brown said. “He runs better than Grady. He has more range than Grady. He has a better arm than Grady. Grady was a grinder. He never gave at-bats away. He wouldn’t fail the same way twice. That’s what made Grady, Grady. And that’s what Anthony has to learn.”

Before this season, failure was a foreign concept for the wonderfully talented 22-year-old center fielder from Southern California. Gose was on baseball’s fast track, ticketed for Toronto next year if he put together a good season with the Bisons. He instead has been confronted by the roughest stretch, and toughest test, of his career.

Suddenly, the same kid who landed on ESPN’s highlight reel after stealing home couldn’t get out of his own way. He was in a miserable 6-for-40 slump in 10 games before Sunday’s matinee against Charlotte in Coca-Cola Field. He was 1 for 4 with a walk in the Bisons’ 11-6 victory Sunday, leaving him with a .227 average through 40 games.

“Right now, I’m probably at the lowest point I’ve ever been in my career,” he said. “It’s been frustrating. It has felt like the longest month of my life, honestly. It’s part of baseball. They say everybody goes through it, but I see guys hitting .390 and it doesn’t look like they’re going through it. It’s definitely back to the learning stage again.”

Clearly, the Blue Jays weren’t overly troubled by his slump. Gose was promoted to the big leagues this morning. But he’ll need to swing the bat much better in Toronto than he did in Buffalo if he wants to stay in the majors.

How he responds over the next few months will determine the timeline on his big-league career. Now that he’s headed for Toronto, he needs out to figure out how to overcome inner demons that have shaken his confidence. It’s yet another necessary layer to stay in the majors and an integral part of the growth process.

Of course, there’s no easy way to mature. Often, major leaps are made when players are forced to overcome adversity. It takes time, sometimes a full season, sometimes more, sometimes never. First, he needs to get his head cleared. Then, he’ll need to start hitting the ball hard again. It will eventually lead to consistent production.

“Can I play? Yeah, I can play,” Gose said. “I’ve put myself into a hole mentally to where I have taken myself out of the equation. This is me battling, searching for what I need to do and how I need to do it. Out of 100 percent, it was 1 percent physical and 99 percent mental. I’ve beaten myself into a hole. Now, I’m trying to climb out of it.”

Gose batted leadoff Sunday. Two pitches into the game, the left-handed hitter opened too soon, swung at a pitch high in the strike zone and popped to short. He twice bounced out to second and did not hit the ball out of the infield. He picked up a single in the third with a drag bunt. When you’re in a slump, any hit is a good hit.

Sometimes, that’s all it takes.

Gose is a pleasant kid with a good sense of humor. He’s brutally honest with himself. He has big-league tools but would be the first to say it means nothing without production. He relied on his natural ability before this season, and why not? It pushed him through the minors and gave him a sniff of the big leagues last season with the Blue Jays.

“Look where tools got me – Triple A in Buffalo,” he said. “That stuff is overrated. That whole prospect stuff, they can save it. It’s all a gimmick. Hey, you either perform or you don’t. Right now, obviously, I’m not. Things change. It’s easy to read into a guy’s numbers and say he’s this or he’s that. It’s a big waste of time.”

Now comes the hard part. Baseball came so easy to him that he didn’t need the same work ethic as others to gain the same results. His quick bat covered deficiencies in his swing and poor pitch selection. He really didn’t know himself as a hitter and never really had a plan when stepping into the batters’ box.

It had seemed too simple.

And it was.

Gose didn’t just fall into a hole. He grabbed a shovel, dug it himself and slipped into a burlap sack. He allowed a four-game hitless streak to seep into his head, essentially talking himself into the slump that lasted three weeks. His biggest problem was drawing up an exit plan because he never needed one.

Gose hit .286 with 10 triples last season in the Pacific Coast League. He was hitting .309 through his first 14 games this season before inexplicably going into a funk. Lately, he’s been simply trying to put his bat on the ball after striking out 15 times in 36 at-bats before Sunday. Earlier this month, he struck out four times twice in a four-game stretch.

His toughest opponent isn’t pitching.

Lately, it’s been himself.

“To some degree, that’s what keeps guys out of the big leagues,” he said. “I could have all the talent in the world, but if I’m not there mentally it’s never going to show up on the field. That’s what’s happening lately. I’ve beat myself down so bad that I haven’t given myself a chance to play on the field.”