What happened Shares of Chesapeake Energy Corporation (NYSE: CHK) sold off in October, ending the month down 9.3%. The primary cause of that decline was a downgrade by analysts at Jefferies who, while noting the company's recent progress, still thought it was well behind rival drillers. So what In early October, the Jefferies team downgraded Chesapeake Energy from hold to sell and set their price target at $2 per share. They did so citing the company's valuation and leverage. Overall, Jefferies said that Chesapeake "has made great strides to simplify the corporate structure and asset base." However, they noted that the company still has more than $9 billion in debt, which along with high fixed costs and a comparatively weak inventory of high-return drilling locations, made them less enthused by its prospects. Image source: Getty Images. Instead, Jefferies thought that investors should buy Concho Resources (NYSE: CXO) and Devon Energy (NYSE: DVN), which they upgraded from hold to buy. They noted that thanks to their prime position in the Permian Basin, both companies had a vast inventory of high-return drilling locations at their disposal. For example, they pointed out that Concho had 30 to 60 years' worth of drilling ahead of it. As a result, both companies appear poised to grow at a rapid rate at current oil and gas prices, with Jefferies noting that Devon is on pace to deliver the best cash flow growth rate in its peer group through 2019. Meanwhile, the two companies have much stronger balance sheets than Chesapeake Energy. In fact, Concho has less than $3 billion in debt despite being nearly $7 billion larger than Chesapeake as measured by enterprise value. Now what Despite its efforts to turn things around, Chesapeake Energy still has a long way to go as it remains well behind financially stronger rivals. Therefore, last month's sell-off isn't a buying opportunity since this stock will likely underperform peers such as Devon and Concho over the long term unless natural gas prices spike. 10 stocks we like better than Chesapeake EnergyWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the 10 best stocks for investors to buy right now... and Chesapeake Energy wasn't one of them! That's right -- they think these 10 stocks are even better buys. Click here to learn about these picks! *Stock Advisor returns as of October 9, 2017Matthew DiLallo has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.