The 34-year-old picked up a calf knock in that game, which Quins won 31-26, with the former Scotland international kicking his heels in an attempt to reach the landmark milestone.
Having seen Welsh rise from the Championship to the heights of European rugby in his three-and-a-half years with the club, Ross admits he'll be a proud man when he does pass into treble figures.
But if he remains fit, Gordon sees no reason why that can't be added to over the coming years.
"I'm now into my fourth season here, but I've been fortunate enough to keep fit for the majority of the time," said Ross.
"I've got no plans to retire just yet, my body has been holding up well and I take the odd week off to recover and that helps, the club have been great in that respect.
"I'm hoping to be involved [against Harlequins] at some point, whether that's from the start or on the bench I'm not sure.
"I've been out of the side recently after picking up a knock on my calf against Harlequins a few weeks ago, but it's been a good chance to rest up and I'm raring to go again.
"I was made aware of the milestone earlier in the week, and I've noted it. It will be great to be involved this week and it will be a very proud moment for me.
"There has been a massive change at the club in the three-and-a-half seasons. The first season we weren't sure whether we were going to be paid, then there was a move to Swansea that never materialised - there's never a dull moment at Welsh.
"But that brings us closer together I think, we work hard as a group and we got our rewards last season."
While Welsh's first foray into Europe hasn't gone past the pool stages, Ross claims their focus has always been on maintaining their Aviva Premiership status.
"I don't think we have tried to hide the fact that the league is the most important thing this year," he added.
"In a way we are disappointed to be out, but there were some tough games against some good teams.
"Maybe we lacked a bit of concentration at times, in the first 20 minutes of the games we struggled but we showed in parts we can compete looking forward."
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