MINNEAPOLIS (WCCO/AP) –Adrian Peterson’s 2-year-old son, who had been in critical condition after being beaten, has died from his injuries, according to Sioux Falls police.

Peterson was in Sioux Falls on Thursday, visiting the boy who police said had been allegedly beaten severely by the man who the mother of the boy is dating.

The child that Peterson was seen with this fall at training camp is not the 2-year-old who has died. WCCO has learned that Peterson discovered he was the victim’s father just a few months ago. It’s not known if he’d met the boy before.

Joseph Robert Patterson, 27, was arrested in the case and is expected to be charged in the coming days with aggravated assault and aggravated battery of an infant, in addition to murder.

Police said Patterson hit the boy in the head with a steel rod. Paramedics found the child in grave condition.

The boy died at 11:43 a.m. at Sanford USD Medical Center in Sioux Falls after being removed from life support, Lincoln County State’s Attorney Tom Wollman said.

Patterson had hurt the child had a past, the prosecutor said, and he’d been convicted of beating a past girlfriend’s child, too.

Vikings coach Leslie Frazier said the star running back has the prayers and support of this football team.

During an impromptu press conference at Winter Park, Peterson said he will be playing on Sunday, and asked for privacy over the situation.

“This is a private matter, and I ask y’all to please respect my privacy and not ask at all about the situation at hand,” Peterson said.

Peterson added, “The good Lord never gives you more than you can bear, can handle — so I’m built tough.”

Fellow running back Toby Gerhart said the team is fully behind Peterson.

“We’re his brothers,” he said. “It’s a chance for him to come here where we rally behind him, support him, whatever he needs.”

Peterson is second in the NFL with 421 yards rushing and first in the league with five touchdowns.

The Vikings (1-3) host the Carolina Panthers (1-3) on Sunday.

After news of the boy’s death spread, kind words poured in from all over. NBA star LeBron James tweeted that his “deepest condolences goes out to Adrian Peterson and his family,” and thousands of the running back’s fans took to social media to express sorrow and sympathy for Peterson.

In response, Peterson thanked his fans for their support, saying “God Bless everyone and thank u so much.”

Thank you to my family, my fans and fans of other teams for their support. — Adrian Peterson (@AdrianPeterson) October 11, 2013

The NFL is a fraternity of brothers and I am thankful for the tweets, phone calls and text messages from my fellow players. — Adrian Peterson (@AdrianPeterson) October 11, 2013

God Bless everyone and thank u so much. — Adrian Peterson (@AdrianPeterson) October 11, 2013

(TM and © Copyright 2013 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2013 CBS Broadcasting Inc. Used under license. All Rights Reserved.This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)