While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a closer look at particularly stock-shaking upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of Devon Energy (NYSE:DVN) gained 1% in premarket trading Monday after Citigroup upgraded the independent energy company from neutral to buy

So what: Along with the upgrade, analyst Robert Morris boosted his price target to $96 (from $75), representing about 21% worth of upside to Friday's close. So while contrarian traders might be turned off by Devon's price strength over the past year, Morris' call could reflect a sense on Wall Street that its production growth prospects still aren't fully baked into the valuation.

Now what: According to Citigroup, Devon's risk/reward trade-off is rather attractive at this point. "[T]he market is not fully recognizing the value of Devon's midstream assets via its ownership interest in Enlink (MLP) and Enlink Midstream (GP) and the potential for future dropdowns from its Canada and Eagle Ford midstream assets," said Morris. "Up until this year, Devon's stock had significantly lagged its peers over the prior five years due to its limited exposure to or inventory of opportunities to grow its oil production, high exposure to low growth natural gas and NGL assets, as well as wide Canadian heavy oil price differentials." Given Citigroup's solid stock-picking track record -- currently ranked in the top 10% of our CAPS community -- resource-savvy Fools might want to take a closer look at Devon.