Connacht made hard work of a game which they controlled for long periods, but three tries in the first 50 minutes were sufficient in the end to see off the Italian outfit, who fought back to gain a bonus point.
Although Eric Elwood was disappointed with his side’s failure to grab a bonus, particularly having led by 31-12 after 47 minutes, Connacht have now moved ahead of both the visitors and Edinburgh with a visit from Aironi next.
Connacht, playing a high-tempo game from the start, were the better of the two sides and led by 18-0 after 24 minutes. A swift backline move saw centre Troy Nathan cross for the first try after three minutes. Ian Keatley converted for a 7-0 lead before adding a penalty after Treviso flanker Manoa Vosawai was binned. Four minutes later scrum-half Frank Murphy added the second try.
Keatley stretched the lead to 18-0 but Connacht conceded a 27th-minute try through Treviso wing Michele Sepe. Willem De Wall added the extras.
Connacht were then penalised for crossing and, from a line-out kicked to touch, the visitors capitalised with a Manoa Vosawai try.
Connacht finished the half with two Keatley penalties, and when Brian Tuohy grabbed the third try early in the second half the home side looked certain to grab a bonus win.
Instead, they made hard work of it.
De Waal’s two penalties started the comeback and Scottish referee Graeme Knox then awarded a penalty try which De Waal converted. It set up a tense finish which Connacht just about survived.
CONNACHT: G Duffy; B Tuohy, N Ta’auso, T Nathan, F Carr; I Keatley, F Murphy; B Wilkinson, S Cronin, J Hagain; M Swift, M McCarthy; A Browne, J O’Connor (capt), R Ofisa.
Replacements: R Loughney for Wilkinson and R Ah You for Hagan (63).
TREVISO: B Williams; M Sepe, E Galon, A Pratichetti, J Maddock; W De Waal, L Nitoglia; I Fernandez Rouyet, F Sbaraglini, L Cittadini; A Pavanello (capt), C Van Zyl; B Vermaak, M Vosawai, M Filippucci.
Replacements: P De Santo for Cittadini, G Padro for Pavanello, M Rizzo for Rouyet, and P Derbyshire for Vosawai (all 48), E Pavanello for Fillippucci and G Garcia for Pratichetti (61).
Referee: G Knox (SRU).