Oppenheimer analyst Brian Nagel downgraded both Home Depot (HD) and Lowe's (LOW) to Perform from Outperform with price targets of $305 and $180, down from $320 and $185, respectively.

Over the near term, the analyst is "increasingly concerned" that the market is becoming "too lax" toward chances of a post-COVID-19 sales growth downshift. Nagel is "concerned somewhat" that the recent outsized comp gains within home improvement might to some extent reflect a demand-pull forward, thereby impacting sales of durables and other items through 2021.

As such, the analyst sees a more modest upside in both stocks going forward.

With that said, the favorable intermediate to longer-term stance for Home Depot and Lowe's is unchanged, Nagel tells investors in a research note.