Dietary strategies are options to mitigate enteric methane from ruminants. This trial has been performed to estimate the production of methane with a sugar-rich forage versus a high-fibre grass. Comparative intake, digestion and methane emission of whole Saccharum officinarum (sugarcane) plant and of Dichanthium sp. hay (from permanent grassland) were studied. Eight Blackbelly rams (40.1 ± 1.4 kg on average) were used in a 2 × 2 crossover design. All the animals received two diets ad libitum: whole sugarcane plant (WSC) supplemented with urea (4.2 g/kg dry matter) and a mature Dichanthium sp. hay (H). Measurements were: voluntary intake, total-tract digestibility, methane production using the SF6 method, rumen concentration of volatile fatty acids, ammonia and protozoa measured by counting. Organic matter intakes were similar between WSC and H treatments, averaging 48.0 g/LW0.75. Intakes of soluble carbohydrate (SC) were higher with WSC than with H (22.7 and 5.8 g/LW0.75, respectively for WSC and H; P < 0.01) .Total tract digestibility (g/kg) differed between WSC and H diets for both organic matter (712 and 647, respectively for WSC and H; P = 0.03) and neutral detergent fibre (510 and 693, respectively for WSC and H; P < 0.01), but not for crude protein (average: 477 g/kg). No difference was recorded between the diets for nitrogen apparently retained. Methane emissions (g/kg Digestible Organic Matter intake (DOM)) differed between diets (34.7 and 53.7, respectively for WSC and H; P < 0.01). Proportion of acetate in total volatile fatty acid (mol/100 mol) was lower with WSC than with H (average: 59 and 77, respectively; P < 0.01), whereas propionate (average: 23 and 15, respectively for WSC and H; P < 0.01) and butyrate (average: 15 and 6, respectively; P < 0.01) proportions were higher. Protozoa population in the ruminal liquid (105/ml) was similar with WSC and H (average: 1.34). In conclusion, our data indicate that in some tropical areas, methane production could differ between grasses and consequently a dietary strategy based on forage management is a realistic option to mitigate enteric methane from ruminants.