Contrasting the success of the sides earlier this summer, McInnes refused to be too downbeat about a promising performance, albeit one which reaped no reward for his newly-promoted side.
In May Killie were facing off against Arbroath in a two-horse Championship race while Rangers were heading to Seville to meet Eintracht Frankfurt for the Europa League trophy after an epic European campaign.
"I think we have got to have a huge dose of realism here,” the Kilmarnock boss said. "A few months ago we were trying to get out of the Championship and Rangers were competing in a European final.
“We are frantically trying to put together a squad that helps us compete and try to bridge the gap. We haven’t spent any money and are trying hard so the first port of call was to come here, frustrate and stay in the game as long as we could.
“We were hoping to get to half-time at 0-0 and to do that I was pleased, the discipline of the team was good.”
Midway through the second half Giovanni van Bronckhorst replaced Antonio Colak, his first goalscorer, with poacher-in-chief Alfredo Morelos, and the switch in scorers saw the second-half goals spread between the pair.
“The goal was self-inflicted,” McInnes rued of the opener. “We had a chance to play forward when Rangers had a high-line, got ourselves into a fankle, the tackle ricochets to Colak and he’s good enough to punish us – one of the few times they got higher up the pitch and it was us giving away possession.
“Then Morelos comes on – they have a rich array of talent and luxury of options.
“No doubt Rangers deserved to win but I thought 2-0 and the second goal a bit harsh.”
After an opening day draw with Dundee United, followed by the trip to Ibrox, Celtic are next at Rugby Park and McInnes added: “I’m disappointed we didn’t manage to do more with first-half possession but our season won’t be defined by playing Rangers at Ibrox.
“Hopefully next time we come here we’ll see improvements but I’m encouraged in the two performances we’ve had.”