HEART OF A TIGER: Growing Up With My Grandfather, Ty Cobb. By Herschel Cobb. ECW Press. 279 pages. $24.95.

The old Ty Cobb legacy is woven into big league lore as tightly as the seams on a new baseball: Hall of Fame hitter, fierce competitor, relentless on and off the field, shrewd Coca-Cola investor, philanthropist. A jerk.

Cobb, who retired in 1928 and died in 1961, still holds the record for highest career batting average (.367). The madman stain remains, too, partly thanks to Al Stump’s significantly discredited biography published in 1994. It was the foundation for the sensationalistic film “Cobb” with Tommy Lee Jones as a tyrannical Ty.

Herschel Cobb aims to change all that with this rarest of baseball profiles, something completely different. His intriguing childhood memoir/tribute makes “The Georgia Peach” sweeter. This Ty Cobb is a caring, life-saving grandfather. A humble hero, he inspires and comforts a boy and two siblings born to a physically abusive father and alcoholic, philandering mother.

“I watched my sister get beaten. She watched me,” Herschel Cobb writes of the household routine. “Watching was terrifying because whoever watched was next.”

It was after Herschel Cobb Sr., Ty’s middle child, died at 33 (Herschel Jr. was 8) that the famous grandfather blossomed into a genuine father figure. Yes, Ty Cobb, the patient mentor, a calm soul skilled in sharing the finer points of fishing, boating and hunting. Through his late teens, Herschel cherishes idyllic summers spent at Lake Tahoe and all the heartfelt letters in between.

There are a few questions unanswered. What took so long? Was Ty Cobb the grandfather trying to make up for his faults as a father? But the tone is consistent.

“Granddaddy had taken Susan, Kit and me under his wing,” Herschel Cobb writes, “and because of what we had built with him, we were going to turn out all right.”

Which is nothing like the infamous nut with spikes flying high into second base and life itself. Some of his strongest language is an entire chapter shot at Stump: “My grandfather’s biographer was interested only in what was negative about Ty Cobb’s family.”

The loving grandson sees Cobb differently. “In my mind,” Herschel Cobb writes, “invincible.”

Reviewer Gene Sapakoff is a Post and Courier sports columnist.