Just as it will not be the friend of the now 38-year-old in coming years, time was not kind to Tua on Saturday night. It took him far too long to get into the fight and once he did it ran out all too quickly. Tua hurt Barrett in the 10th round but then backed off. In the 11th the strapping American was teetering with his chin exposed only to be saved by the bell. Tua put his man down in the final round but Barrett bravely answered a slowish count and somehow clung on for the final 50 seconds.
That would have been more than enough time for Tua anywhere near his prime to finish the job.
If Tua's promoter Cedric Kushner is correct and the defeat cost Tua a bout with Wladimir Klitschko, Barrett has probably saved him from a serious beating. This David Tua would not survive six rounds with the Russian.
Tua has found his level and at this level of conditioning it is slightly below that of Barrett - another fighter who no longer resides in the upper echelon of a fairly thin division.
That does not mean it is the end for this country's greatest heavyweight. We're not talking Micky Ward-Arturo Gatti, but in Barrett, Tua has a fine rival. Both fights have been compelling, dramatic and highly entertaining. Saturday night's bout more than justified the $30 pay-TV price tag.
Tua-Barrett III wouldn't lack for audience appeal but, having escaped from 24 rounds with one of the biggest punchers of the modern era with pride and faculties intact, Barrett might not be so enthusiastic. He indicated as much when he said he was focused on having a holiday before beginning a professional wrestling career. Tua needed just one word when asked for his thoughts on a rematch - "Please".
Whether that happens might well come down to how the pay-per-view numbers from this fight stack up. Barrett would certainly command a far greater share of the revenue than he is reported to have received this time around, which might be enough to get him back in the ring.
Let's hope so. A third and final fight would be a fine way for these two ageing warriors to end their careers.