This year’s Super Bowl wasn’t just a showcase for the Kansas City Chiefs and San Francisco 49ers—or halftime performers Shakira and Jennifer Lopez. It was also an opportunity for the four national wireless carriers to highlight their 5G network capabilities, and a large-scale test of their LTE networks’ performance under pressure.

Global Wireless Solutions had its network testing specialists on-hand at Hard Rock Stadium in Miami, Florida, using Samsung Galaxy S10 5G devices to test the 5G networks of AT&T, Sprint, T-Mobile and Verizon. GSW conducted tests at the GameDay Fan plaza where pre-game festivities were held, as well as inside the stadium in a variety of locations in the concourses and seating areas.

“GWS test results show that although mobile operators came prepared to show off their 5G networks, not all were successful in providing the hyped throughputs that have been boasted,” the benchmarking company concluded.

AT&T had the highest average 5G download speed over the testing period, at 337 Mbps, while Verizon provided the maximum observed 5G throughput, at 924 Mbps. Comparatively, Verizon’s average 5G download speed was 200 Mbps and the maximum 5G throughput that GWS saw on AT&T’s 5G network was 878 Mbps. T-Mobile US had an average 5G download speed of just 31 Mbps, with a maximum throughput of 175 Mbps.

Meanwhile, Sprint’s 5G network was “tested for but not found during any tests,” GWS found. Sprint’s 4G network averaged 29 Mbps in the downlink.

GWS said that it observed 5G millimeter-wave beamforming used by AT&T, Verizon and T-Mobile US, with an average of 8-9 beams per cell, and that the average 5G bandwidth on all three of those networks was 100 megahertz.

Read more of the details from GWS’ test results here. You can also compare them to crowd-sourced Ookla Speedtest data from the big game, which found an average mean download speed for Verizon 5G of nearly 650 Mbps and insufficient speedtest data to draw conclusions about AT&T’s 5G network—but found average speeds for Sprint 5G of about 225 Mbps.