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Microsoft's tablet partnership with the National Football League has not always been smooth.

After Microsoft struck a reported $400 million deal in 2013 with the NFL to have its Surfaces exclusively on team sidelines for reviewing plays, TV commentators kept referring to them as "iPads." At the time, it was said that networks were constantly reminding their talkers that the Surface looks nothing like an iPad and should therefore be referred to by its actual name.

Microsoft's tablet seemed to suffer another public black eye Sunday as TV viewers of the AFC championship game Sunday between the Denver Broncos and New England Patriots were told that the tablets on the Patriots' sidelines had failed.

"They're having some trouble with their Microsoft Surface tablets," CBS' sideline reporter Evan Washburn reported during the game. "On the last defensive possession the Patriots' coaches did not have access to those tablets to show pictures to their players. NFL officials have been working at it. Some of those tablets are back in use, but not all of them. A lot of frustration that they didn't have them on that last possession." (Editors' note: CNET is owned by CBS.)

The outage, which struck during the first half, was brief, and the Patriots' tablets were soon restored to working order. A Microsoft spokesman blamed the problem on a network connectivity issue rather than a tablet malfunction.

"Our team on the field has confirmed the issue was not related to the tablets themselves but rather an issue with the network," the company said in a statement Sunday. "We worked with our partners who manage the network to ensure the issue was resolved quickly."

On Monday, the NFL issued another statement to make clear that Microsoft's Surface wasn't responsible for the disconnect.

"Near the end of the 1st quarter, we experienced an infrastructure issue on the Patriots sideline that impacted still photos for the coaching tablets," NFL spokesman Brian McCarthy said in a statement Monday. "The issue was identified as a network cable malfunction and was resolved during the 2nd quarter. The issue was not caused by the tablets or the software that runs on the tablets. We have experienced no issues with the tablets this season. Any issues were network related."

The Broncos, who apparently didn't suffer a tablet interruption, were allowed to continue using their tablets because NFL rules require the tablets to be shut down for both teams only if they malfunction before the game begins.

Even though the Surface wasn't ultimately to blame for Sunday's disconnect, it wasn't the first time the tech titan's tablet has taken a beating on the sidelines. During a game last month between the Cleveland Browns and the San Francisco 49ers, controversial Browns quarterback Johnny Manziel, aka Johnny Football, clutched his Surface in frustration and began banging the device repeatedly against his head.

Unfortunately for Microsoft, tablets in general are also taking something of a beating in the marketplace. Consumers aren't snapping up slates as fast as they did a few years ago, according to data collected by market researcher IDC. Worldwide tablet shipments declined more than 12 percent during the third quarter of 2015, IDC reported in October, their fourth straight quarterly decline.

Updated at 2:45 p.m. PT with Microsoft comment.

Updated 1/25, at 2:40 p.m. PT with further Microsoft comment.