Is Sage Group Plc a once-in-a-decade investment opportunity? The stock has fallen 33% since January 2025, fueled by fears that AI might disrupt its business. But what if these fears are misplaced? In my opinion, Sage is a high-quality FTSE 100 stock with a strong track record of double-digit earnings growth, and it's well-positioned to benefit from the launch of new AI tools and services. The company's AI-powered features are already helping finance teams accelerate cash flows and close the books faster, and it expects operating margins to trend upwards over time. While economic weakness could be a near-term risk, the stock looks dirt cheap at 15 times next year's forecast earnings, and it has a very well-supported forward dividend yield of 2.8%. I bought Sage shares earlier this year, and after the strong update in May, I'm considering buying more. In fact, I believe there's a once-in-a-decade opportunity here, and investors could do the same. But should you invest £5,000 in Sage Group Plc right now? When investing expert Mark Rogers and his team have a stock tip, it can pay to listen. After all, the flagship Twelfth Magpie Share Advisor newsletter he has run for nearly a decade has provided thousands of paying members with top stock recommendations from the UK and US markets. And right now, Mark thinks there are 6 standout stocks that investors should consider buying. So, is Sage Group Plc a good investment? I think so, and I'm optimistic about its future prospects. But as always, do your own research and consult with a financial advisor before making any investment decisions.