Craig Brewster took a back-seat in his first game in charge as Caley Thistle eliminated a stubborn Arbroath from the CIS Insurance Cup.
Romanian striker Marius Niculae scored twice in each half and Dennis Wyness' 64th minute goal completed the victory for the Highland side.
Bryan Scott gave the visitors some hope after 71 minutes, but the Red Lichties were unable to overturn the deficit.
Brewster will be content that his first match in charge didn't end in upset.
Stand-in Inverness captain Ross Tokely made his mark early on in the game with a 35-yard effort, then with a clumsy challenge on Scott.
After 19 minutes, Barry Wilson came close with an effort from Don Cowie's cross which clipped keeper Morrison's crossbar.
Niculae was eager to break his duck, and after being thwarted twice in quick succession by Morrison his luck changed after 34 minutes.
A short pass from Wyness allowed the Romanian striker to notch up his first goal in Scottish football with a low 25-yard drive.
Wilson came close to doubling the Inverness advantage after 58 minutes, when McBain's cross from the left picked out the midfielder on the edge of the six-yard box and Wilson's diving header hit the right post.
Wyness grabbed his first goal since January with the second strike of the night after 64 minutes when he collected Duncan's cross from the right, then turned and fired home from close range.
Just as Inverness looked safe, Arbroath pulled a goal back after 71 minutes, when Scott exploited an error by Stuart McCaffrey to follow up his initial effort and sidefoot past Fraser.
The joy was short-lived for the Lichties when Niculae scored a delightful free-kick from 25 yards.
Inverness CT: Fraser, Tokely, Watt, McCaffrey, McBain (Morgan 79), Wilson (Rankin 79), Black, Duncan, Cowie, Niculae (McAllister 85), Wyness. Subs Not Used: Ridgers, McDonald.
Booked: McAllister, Duncan.
Goals: Niculae 34, Wyness 64, Niculae 74.
Arbroath: Morrison, Stuart McKay, Ferguson, Raeside (Rennie 77), Bishop, Tully, Hegarty (Webster 62), Scott, Tosh, Sellars, Watson (Reilly 75). Subs Not Used: Black, Wight. Booked: Scott.
Goals: Scott 71.
Ref: S Finnie