Affidavits say the victim’s girlfriend heard the confrontation unfold as a custody exchange outside a San Antonio YMCA turned violent.
SAN ANTONIO, Texas — The most striking detail in the criminal case over a stabbing outside a San Antonio YMCA is not just the knife attack police describe, but the phone line that was still open when it happened. Investigators say the victim’s girlfriend heard enough to place two suspects at the scene and capture the moment fear turned into violence.
That phone call sits near the center of the case now that both suspects have been charged. Police allege Abel Ali Rivas, 27, stabbed Oscar Javier Barbosa, 32, during a Feb. 19 custody exchange at the Davis-Scott Family YMCA, while Melanie Sierra Gomez, 31, helped set up the encounter and kept Barbosa from escaping. The affidavits cited by San Antonio media outlets give investigators three linked accounts: Barbosa’s own statement, the girlfriend’s account of what she heard, and police allegations about how Gomez directed Barbosa in and out of the building before the stabbing.
According to the charging records described by local media, Barbosa had gone to the YMCA on Iowa Street to pick up the two children he shares with Gomez. He was in contact with Gomez by phone that evening. Police say she first told him to go inside, then called again and told him to return outside. During that stretch, Barbosa also called his current girlfriend. That detail later mattered because the woman told investigators she stayed on the line as Barbosa walked back into the parking lot. She said she recognized Rivas’ voice because she had once been in a 10-year relationship with him. Then, according to the affidavit, she heard Barbosa say, “Are you going to stab me over this?” before the call disconnected.
The prosecution narrative uses that moment to do several jobs at once. It places Rivas at the scene, supports Barbosa’s claim that the meeting had turned hostile, and gives police a witness who was not physically present but says she heard the exchange in real time. It also helps explain why investigators viewed Gomez’s alleged role as more than incidental. Officers say she approached as the argument grew, accused Barbosa of getting his new girlfriend pregnant and told Rivas to proceed. The affidavit says Rivas then stabbed Barbosa several times in the torso and arms while Gomez pinned Barbosa against a car. Police described the injuries as serious but not life-threatening. Officers responding about 6:40 p.m. found Barbosa wounded outside the YMCA and sent him to a hospital.
Seen through the affidavit, the location matters because it was not a random meeting point. The Davis-Scott Family YMCA is a known community site on the city’s East Side, and the exchange appears to have followed a family routine tied to the children. Yet several important facts remain outside the public record. The documents summarized by reporters do not say whether any surveillance video captured the parking lot. They do not indicate whether the children were close enough to witness the attack. They also do not show whether either suspect has publicly responded to the allegations in court. For now, the published account is almost entirely the state’s version of events, built from interviews, injury reports and the claim that a phone call preserved the encounter’s final seconds before the stabbing began.
Police say the violence did not end with the knife wounds. After the attack, Rivas allegedly fled in Barbosa’s running vehicle. Gomez, investigators said, stayed behind briefly, continuing to insult Barbosa’s current girlfriend before leaving. Barbosa later identified both suspects, and local outlets reported that he also picked them out in photo lineups. Gomez was arrested first, days after the incident, and later posted an $85,000 bond. Rivas was arrested about a month later and remained jailed on a total of $105,000 bond, including a separate amount connected to a controlled-substance count. Both are charged with aggravated assault with a deadly weapon, the same offense police say fits the alleged roles of the person holding the knife and the person who helped carry out the assault.
This version of the story is less about a sudden parking-lot dispute than about evidence and sequence. Investigators appear to be drawing a line from the calls before the attack, to the words heard on the live call, to the actions after the stabbing. That chain may become critical if the case moves toward indictment or trial. Defense lawyers could challenge the girlfriend’s identification of Rivas’ voice, dispute Barbosa’s account, or argue that the event escalated in a way not reflected in the affidavits. Prosecutors, on the other hand, are likely to treat the recorded timeline of movements and statements as proof that Barbosa was guided into a confrontation already waiting for him.
As the case moves ahead, the unanswered question is whether the phone call remains the strongest piece of outside corroboration or whether investigators add video, forensic records or more witness statements. For now, the open line remains one of the clearest windows into what police say happened in the YMCA parking lot.
Author note: Last updated April 16, 2026.