The Boks raced to a commanding 28-3 halftime lead, but failed to maintain their momentum in the second half as Italy fought back strongly.
Erasmus did not hide his disappointment with the performance, acknowledging that the Springboks let their standards slip.
"Italy did leave a few of their big players at home, so they had a few young players playing with nothing to lose, and they made it a proper fight.
"It was a fiercely contested test match, but the performance was very frustrating," bemoaned Rassie Erasmus.
Reflecting on the first Test of the season, Erasmus admitted that it’s preferable to iron out issues early rather than deeper into the campaign.
Despite dominating possession and territory in the first half, the Springboks failed to fully capitalise.
The second half saw Italy grow into the game, and Erasmus pointed to below-par lineouts as a key factor in the disrupted performance.
"Our lineout was riddled with mistakes, and the mistakes were made by a variety of players. I would love to pinpoint the reason for our lineout not functioning as it should. Luckily, all of these mistakes are fixable, and it is still early in the season," stated the Bok coach.
Italy scored three second-half tries, including impressive finishes from Pablo Dimcheff and Niccolò Cannone, cutting South Africa’s lead down to 35-24 at one stage and putting real pressure on the hosts.
Erasmus praised the visitors’ resilience and work rate, admitting the Boks were tested in ways they didn’t anticipate.
The much-vaunted ‘bomb squad’ failed to make the usual impact at Loftus, as a full tight-five substitution didn’t yield the intended results.
Erasmus admitted the tactic, designed to lift intensity in the latter stages, fell flat on the day.
He noted that while the strategy has worked in the past, it simply didn’t come together this time.