The history of Mexican baseball began in Sonora. That has been accepted as an officially sanctioned fact. However, this fact has been built upon foundation of inaccurate and unreliable documentation.For many years, has been widely accepted that game was introduced to Sonora when military vessel arrived in port of Guaymas in May 1877. The sailors asked permission to land, clean nearby ground, and start new game: baseball.1This account was first published in book El Beisbol en Sonora by Miguel Durazo. In it, natives rapidly gathered around event and gave way to a happy laughter when catcher wore his mask and adopted his usual posture.2Afterwards, natives would learn game and spread to neighboring cities like Hermosillo, Magdalena, Ures, and rest of Mexican Northwest. Even if there were earlier accounts, Guaymas version appeared to be most detailed and important one.However, this version of events is based entirely upon oral tradition. Its details were transmitted by Torcuato Marcor, alleged witness of historic event that... was played among sailormen of Montana, who were divided into two teams. Unfortunately, was burned at port's bay (of Guaymas) in 1878. The Newbern was another unit that replaced in trips to our port and, like these units, had its own organized baseball team. They [the Newbern's crew] also landed to play famous game.3Durazo concludes Marcor's account by asserting that Guaymas is the cradle of Mexican Baseball.4However, after scrutinizing several elements of story, is clear that they cannot be part of same event. Consequently, this version of events must be judged at best inconsistent, at worst apocryphal.It is imperative to emphasize that Torcuato Marcor, witness upon whom story has been based, was born in 1867 and his testimony was given around 1950. He was attempting to recall events from which he was more than 70 years removed.According to Marcor, was military vessel. He makes clear in two aspects of story. First, when he says that he was lucky to know some ships from Uncle Sam's Navy that made regular trips to port. In one of those visits, arrived. Secondly, he states that all these units, like ground troops, have their organized teams.5That is first detectable mistake in version. The was not military ship. In historical registers of United States Navy, first warship that was named Montana was not commissioned until April 1905.6Actually, that navigated to Guaymas was steamer that transported mail, passengers, and other cargo. Its route was from San Francisco to Cortez' Sea, arriving at Mexican ports like La Paz, San Blas, Mazatlan, and Guaymas and finishing its itinerary at delta of Colorado River. Afterwards, would sail back to San Francisco following same route.Steamships that, like Montana, traveled from San Francisco to those ports made easier for natives of Mexican northwest to travel to California to study or engage in business.The biggest mistake in this story lies in assumption that was sailing in 1877. Confusion about sinking of this ship has given rise to several divergent accounts. According to Durazo, the burned down at Guaymas bay in 1878.7Alfonso Iberri, in his book El Viejo Guaymas, agrees with Durazo that the burned down inside bay soon after lifting its anchor to sail back to San Francisco in 1878.8 Angel Encinas, in his book El Beisbol en Hermosillo, refers to document sent to state's governor informing him about sinister event, and affirms that it was not in 1878 but still 1877, night of December 14th.9Actually, fire and sinking of happened night of December 14, 1876. …