The Rangers said through a team spokesman that they are "aware of a situation but have no further comment at this time." The team has scheduled a news conference at Rangers Ballpark in Arlington at 1 p.m. CT.
Hamilton drank alcohol at Sherlock's Pub & Grill in Dallas Monday, sources familiar with the situation told The Dallas Morning News. According to the sources, teammate Ian Kinsler was also at the bar. The newspaper reported that eyewitnesses said he appeared to be there to convince Hamilton to go home.
A source says Hamilton told the Rangers of the relapse the next day and that the team has been working to help him in recovery-related support. The source said the incident was strictly about alcohol and that no drugs were involved. Sources said Hamilton plans to issue a written statement or talk publicly about the incident soon, maybe as early as Friday.
Hamilton's wife Katie did post a couple of messages on her Twitter account.
"Truly appreciate all the encouraging & supportive tweets we've been getting," one tweet said. "God is Faithful and forgives -- so thankful that you all are."
Another read: "Showing us such love and encouragement during this time."
It was still unclear exactly what circumstances led Hamilton to suffer his relapse, which was reported by the Morning News earlier Thursday, but he has battled to stay sober since an incident in a Tempe, Ariz., bar a little more than three years ago.
Then, he was photographed drinking with several women and those pictures went viral about seven months later. Hamilton spoke to the media about it at that time and apologized, saying: "I hate that this happened."
When that occurred, Hamilton immediately called the Rangers and Major League Baseball. He passed a drug test shortly thereafter and went through league-sanctioned counseling. Hamilton also made sure his support system was fully in place, including having Johnny Narron, his "accountability partner" at the time, with him at spring training and through the rest of the season.
Hamilton, 30, was banned from baseball in 2003 for drug and alcohol use while in the Tampa Bay organization. He was reinstated in 2006 and is drug tested three times a week.
Right now, Hamilton and the Rangers are still in the process of finding a new "accountability partner" after Narron left the club to become the Milwaukee Brewers' hitting coach. Hamilton's father-in-law, Michael Dean Chadwick, was planning on assuming that role for Narron but didn't want to leave his teenage daughter as she gets closer to finishing high school.
The Rangers have expressed an interest in signing Hamilton to a long-term extension, though both sides agreed that if a deal wasn't in place by the time spring training starts later this month, that they wouldn't talk during the season to avoid potential distraction.
Hamilton, the 2010 American League MVP, has worked to avoid even the smell of alcohol, something his teammates have respected. They have even catered their postseason celebrations for him (and former teammate C.J. Wilson, who also did not want to be around alcohol) by having ginger ale and water showers before breaking out the champagne after winning a playoff series.
When discussing his last relapse in August 2009, Hamilton said it was the first drink he'd had since Oct. 6, 2005, the day he vowed to stay sober. Drugs and alcohol helped delay Hamilton's track to the big leagues despite being the No. 1 overall draft pick in 1999 by the Tampa Bay Rays. He did not make his major league debut until 2007 with the Cincinnati Reds.
Richard Durrett covers the Rangers for ESPNDallas.com. Information from ESPN.com's Jerry Crasnick contributed to this report.