Recognized as a great fielder, Bergen tended to obsess about minor problems and displayed an argumentative personality, traits that negatively affected his enjoyment of the game.

On July 11, still in the midst of the season, he married Hattie Gaines, who had moved to North Brookfield a year before to work at a flour mill.

[3][5] In 1897, Bergen received a greater share of the catching duties, playing 87 games to Ganzel's 30; a third catcher, Fred Lake, only made 19 appearances.

[3][10] Nichols credited Bergen with helping the team win: "Baltimore beat us the next three years, after we lost (catcher Charlie) Bennett.

Bergen played all nine innings of the team's second-to-last game of the year on October 13 and did not mention a broken hip in a visit to his doctor after the season.

The Sandusky Star and The Bangor Daily Whig and Courier pinned the blame for the second-place finish on a rift that had developed between the sullen Bergen and his teammates.

[3] William Nack of Sports Illustrated wrote in 2001 that Bergen was "a nimble fielder with a bullwhip arm who could snap the ball to second base without so much as moving his feet.

His eye was always true, and his movements so quick and accurate in throwing that the speediest base runners [...] never took chances when Bergen was behind the bat.

"[3] Bergen's teammates appreciated his strong arm and hustling style of play, but relations between the catcher and the team soured quickly.

"[3] While the team was on a road trip to St. Louis in 1898, Bergen slapped teammate Vic Willis while the ballclub was eating breakfast.

The team's mixed emotions were expressed by an anonymous Boston player quoted in the press: "He has made trouble with a good many of the boys and we just give him a wide berth.

Soden and manager Frank Selee granted him time off until he felt recovered enough to rejoin the team; Bergen was back with the club after two weeks.

[3][12][13] On July 20, 1899, Bergen silently walked off the team's train at the beginning of a road trip, returning to North Brookfield and leaving Boston with just a backup catcher (Clarke) during a heated pennant race.

Boston Globe reporter Tim Murnane journeyed to North Brookfield to convince Bergen to come back; the catcher complained that his teammates were mistreating him, that Selee would not give him time off to be with his family, and that he was battling injuries that could only be dealt with by his local physician, Dr. Louis Dionne.

On October 9, Bergen had to be removed from a game when he dodged the pitches rather than catching them, claiming that he was preoccupied with avoiding knife thrusts from an invisible assailant.

However, he refused to take any of the bromides prescribed by his doctor, explaining, "I thought someone in the National League had found out that you were my family physician and had arranged to give me some poison.

"[3][12] Kaense, Spahn, and Johnson's 2004 book on the Boston Braves recounts that, after Bergen's son's death, the player "would catch a few games, then ask Selee if he could return home for a few days.

Most of his teammates were avoiding him completely by the end of the year, and several players said they would not return to the Beaneaters in 1900 if the increasingly erratic Bergen was still with the club.

[16] The medical examiner reported that Bergen killed his wife and two children with an axe, then used a straight razor to forcefully cut his own throat.

The appearance of the little girl [his 6-year-old daughter found on the kitchen floor next to Bergen] also showed that a number of savage blows had been rained upon the top and side of her head.

[2] Following Bergen's death, media outlets reported that he had been subject to "fits of melancholy" and had "showed signs of insanity" in the fall of 1899.

[17] After examining contemporary accounts, the Harvard Medical School's Dr. Carl Salzman felt that Bergen likely had schizophrenia with possible manic depression.

[12] Baseball historian Frank Russo wrote, "If he were alive today, he most surely would be diagnosed with some sort of clinical depression or perhaps borderline personality disorder," adding that he was showing strong signs of schizophrenia in late 1899.

[2] Bergen and his wife and children were buried at Saint Joseph's Cemetery on Bell Street in North Brookfield; his grave remained unmarked for several years.

[2] In 1934, Mack and George M. Cohan, both of whom had ties to North Brookfield, helped raise funds to erect a granite memorial to Bergen.

[6][18] The death of Bergen prevented him from ever playing against his brother Bill, who was also a major league catcher for the Cincinnati Reds and the Brooklyn Superbas from 1901 to 1911.